[Xiaomi Mi A2 / 6X Questions & Answers] tecknight:
Try:

fastboot oem device-info

Really, fastboot getvar all shows nothing ?

My Xiaomi shows this:

C:\Program Files (x86)\Tiny ADB and Fastboot>fastboot getvar all

(bootloader) DP:0x0

(bootloader) token:VQEBIQEQ1kekQ0NylG8kUtJFKdSXfwMHY3VydGFuYQIEHRKPsg

(bootloader) parallel-download-flash:yes

(bootloader) hw-revision:10001

(bootloader) unlocked:yes

(bootloader) off-mode-charge:1

(bootloader) charger-screen-enabled:1

(bootloader) battery-soc-ok:yes-

(bootloader) battery-voltage:3884

(bootloader) version-baseband:

(bootloader) version-bootloader:

(bootloader) erase-block-size: 0x1000

(bootloader) logical-block-size: 0x1000

(bootloader) variant:SM_ UFS

(bootloader) partition-type:fsc:raw

(bootloader) partition-size:fsc: 0x20000

(bootloader) partition-type:fsg:raw

(bootloader) partition-size:fsg: 0xA00000

(bootloader) partition-type:modemst2:raw

(bootloader) partition-size:modemst2: 0x200000

(bootloader) partition-type:modemst1:raw

(bootloader) partition-size:modemst1: 0x200000

(bootloader) partition-type:ALIGN_TO_128K_2:raw

(bootloader) partition-size:ALIGN_TO_128K_2: 0x1A000

(bootloader) partition-type:bootbak:raw

(bootloader) partition-size:bootbak: 0x8000000

(bootloader) partition-type:dtbobak:raw

(bootloader) partition-size:dtbobak: 0x1800000

(bootloader) partition-type:vbmetabak:raw

(bootloader) partition-size:vbmetabak: 0x10000

(bootloader) partition-type:dtbo:raw

(bootloader) partition-size:dtbo: 0x1800000

(bootloader) partition-type:boot:raw

(bootloader) partition-size:boot: 0x8000000

(bootloader) partition-type:vbmeta:raw

(bootloader) partition-size:vbmeta: 0x10000

(bootloader) partition-type:catecontentfv:raw

(bootloader) partition-size:catecontentfv: 0x100000

(bootloader) partition-type:catefv:raw

(bootloader) partition-size:catefv: 0x80000

(bootloader) partition-type:secdata:raw

(bootloader) partition-size:secdata: 0x7000

(bootloader) partition-type:uefivarstore:raw

(bootloader) partition-size:uefivarstore: 0x80000

(bootloader) partition-type:multiimgqti:raw

(bootloader) partition-size:multiimgqti: 0x8000

(bootloader) partition-type:multiimgoem:raw

(bootloader) partition-size:multiimgoem: 0x8000

(bootloader) partition-type:storsec:raw

(bootloader) partition-size:storsec: 0x20000

(bootloader) partition-type:logdump:raw

(bootloader) partition-size:logdump: 0x4000000

(bootloader) partition-type:cateloader:raw

(bootloader) partition-size:cateloader: 0x200000

(bootloader) partition-type:logfs:raw

(bootloader) partition-size:logfs: 0x800000

(bootloader) partition-type:toolsfv:raw

(bootloader) partition-size:toolsfv: 0x100000

(bootloader) partition-type:limits:raw

(bootloader) partition-size:limits: 0x1000

(bootloader) partition-type:splash:raw

(bootloader) partition-size:splash: 0x20A4000

(bootloader) partition-type:spunvm:raw

(bootloader) partition-size:spunvm: 0x800000

(bootloader) partition-type:apdp:raw

(bootloader) partition-size:apdp: 0x40000

(bootloader) partition-type:dip:raw

(bootloader) partition-size:dip: 0x100000

(bootloader) partition-type:devinfo:raw

(bootloader) partition-size:devinfo: 0x1000

(bootloader) partition-type:uefisecappbak:raw

(bootloader) partition-size:uefisecappbak: 0x200000

(bootloader) partition-type:imagefvbak:raw

(bootloader) partition-size:imagefvbak: 0x200000

(bootloader) partition-type:qupfwbak:raw

(bootloader) partition-size:qupfwbak: 0x10000

(bootloader) partition-type:devcfgbak:raw

(bootloader) partition-size:devcfgbak: 0x20000

(bootloader) partition-type:cmnlib64bak:raw

(bootloader) partition-size:cmnlib64bak: 0x80000

(bootloader) partition-type:cmnlibbak:raw

(bootloader) partition-size:cmnlibbak: 0x80000

(bootloader) partition-type:keymasterbak:raw

(bootloader) partition-size:keymasterbak: 0x80000

(bootloader) partition-type:dspbak:raw

(bootloader) partition-size:dspbak: 0x2000000

(bootloader) partition-type:ablbak:raw

(bootloader) partition-size:ablbak: 0x800000

(bootloader) partition-type:mdtpbak:raw

(bootloader) partition-size:mdtpbak: 0x2000000

(bootloader) partition-type:mdtpsecappbak:raw

(bootloader) partition-size:mdtpsecappbak: 0x400000

(bootloader) partition-type:bluetoothbak:raw

(bootloader) partition-size:bluetoothbak: 0x100000

(bootloader) partition-type:modembak:raw

(bootloader) partition-size:modembak: 0x10000000

(bootloader) partition-type:hypbak:raw

(bootloader) partition-size:hypbak: 0x80000

(bootloader) partition-type:tzbak:raw

(bootloader) partition-size:tzbak: 0x400000

(bootloader) partition-type:aopbak:raw

(bootloader) partition-size:aopbak: 0x80000

(bootloader) partition-type:uefisecapp:raw

(bootloader) partition-size:uefisecapp: 0x200000

(bootloader) partition-type:imagefv:raw

(bootloader) partition-size:imagefv: 0x200000

(bootloader) partition-type:qupfw:raw

(bootloader) partition-size:qupfw: 0x10000

(bootloader) partition-type:devcfg:raw

(bootloader) partition-size:devcfg: 0x20000

(bootloader) partition-type:cmnlib64:raw

(bootloader) partition-size:cmnlib64: 0x80000

(bootloader) partition-type:cmnlib:raw

(bootloader) partition-size:cmnlib: 0x80000

(bootloader) partition-type:keymaster:raw

(bootloader) partition-size:keymaster: 0x80000

(bootloader) partition-type:dsp:raw

(bootloader) partition-size:dsp: 0x2000000

(bootloader) partition-type:abl:raw

(bootloader) partition-size:abl: 0x800000

(bootloader) partition-type:mdtp:raw

(bootloader) partition-size:mdtp: 0x2000000

(bootloader) partition-type:mdtpsecapp:raw

(bootloader) partition-size:mdtpsecapp: 0x400000

(bootloader) partition-type:bluetooth:raw

(bootloader) partition-size:bluetooth: 0x100000

(bootloader) partition-type:modem:raw

(bootloader) partition-size:modem: 0x10000000

(bootloader) partition-type:hyp:raw

(bootloader) partition-size:hyp: 0x80000

(bootloader) partition-type:tz:raw

(bootloader) partition-size:tz: 0x400000

(bootloader) partition-type:aop:raw

(bootloader) partition-size:aop: 0x80000

(bootloader) partition-type:ddr:raw

(bootloader) partition-size:ddr: 0x100000

(bootloader) partition-type:cdt:raw

(bootloader) partition-size:cdt: 0x20000

(bootloader) partition-type:ALIGN_TO_128K_1:raw

(bootloader) partition-size:ALIGN_TO_128K_1: 0x1A000

(bootloader) partition-type:xbl_configbak:raw

(bootloader) partition-size:xbl_configbak: 0x20000

(bootloader) partition-type:xblbak:raw

(bootloader) partition-size:xblbak: 0x700000

(bootloader) partition-type:xbl_config:raw

(bootloader) partition-size:xbl_config: 0x20000

(bootloader) partition-type:xbl:raw

(bootloader) partition-size:xbl: 0x700000

(bootloader) partition-type:userdata:f2fs

(bootloader) partition-size:userdata: 0x1A2CDD3000

(bootloader) partition-type:super:raw

(bootloader) partition-size:super: 0x200000000

(bootloader) partition-type:ffu:raw

(bootloader) partition-size:ffu: 0x800000

(bootloader) partition-type:gsort:raw

(bootloader) partition-size:gsort: 0x1000000

(bootloader) partition-type:exaid:raw

(bootloader) partition-size:exaid: 0x18000000

(bootloader) partition-type:cache:ext4

(bootloader) partition-size:cache: 0x18000000

(bootloader) partition-type:metadata:raw

(bootloader) partition-size:metadata: 0x1000000

(bootloader) partition-type:vbmeta_systembak:raw

(bootloader) partition-size:vbmeta_systembak: 0x10000

(bootloader) partition-type:vbmeta_system:raw

(bootloader) partition-size:vbmeta_system: 0x10000

(bootloader) partition-type:recoverybak:raw

(bootloader) partition-size:recoverybak: 0x8000000

(bootloader) partition-type:recovery:raw

(bootloader) partition-size:recovery: 0x8000000

(bootloader) partition-type:cust:raw

(bootloader) partition-size:cust: 0x40000000

(bootloader) partition-type:minidump:raw

(bootloader) partition-size:minidump: 0x8000000

(bootloader) partition-type:frp:raw

(bootloader) partition-size:frp: 0x80000

(bootloader) partition-type:keystore:raw

(bootloader) partition-size:keystore: 0x80000

(bootloader) partition-type:misc:raw

(bootloader) partition-size:misc: 0x100000

(bootloader) partition-type:persist:raw

(bootloader) partition-size:persist: 0x2000000

(bootloader) partition-type:ssd:raw

(bootloader) partition-size:ssd: 0x2000

(bootloader) secure:yes

(bootloader) serialno:591c2700

(bootloader) anti:1

(bootloader) cpuid:0x1d128fb2

(bootloader) product:curtana

(bootloader) is-userspace:no

(bootloader) max-download-size:805306368

(bootloader) kernel:uefi

all:

Finished. Total time: 0.162s