[Huawei Mate 9 Questions & Answers] zgfg:
Unwanted (system) apps can be disabled or uninstalled (for default/current user) by ADB commands (again, root not required) - for complete guides, see here:

https://www.xda-developers.com/uninstall-carrier-oem-bloatware-without-root-access/

https://xdaforums.com/apps/magisk/mod-magisk-v1-universal-systemless-t3432382/post80288347

Batch script with examples of some Huawei system apps that can be disabled is given here:

ECHO OFF
CLS

adb wait-for-device devices
PAUSE

ECHO List packages
adb shell pm list packages
PAUSE

ECHO List disabled packages
adb shell pm list packages -d
PAUSE

ECHO Disable System Update
adb shell pm disable-user com.huawei.android.hwouc
PAUSE

ECHO Disable Files
REM adb shell pm disable-user com.huawei.hidisk
PAUSE

ECHO Disable HiCare
adb shell pm disable-user com.huawei.phoneservice
PAUSE

ECHO Disable HiSearch
adb shell pm disable-user com.huawei.search
PAUSE

ECHO Disable Market Feedback Agent
adb shell pm disable-user com.google.android.feedback
PAUSE

ECHO Disable Tips
adb shell pm disable-user com.huawei.tips
PAUSE

ECHO Disable Duo
adb shell pm disable-user com.google.android.apps.tachyon
PAUSE

ECHO Disable GMail
adb shell pm disable-user com.google.android.gm
PAUSE

ECHO Disable Google
adb shell pm disable-user com.google.android.googlequicksearchbox
PAUSE

ECHO Disable Google Play Music
adb shell pm disable-user com.google.android.music
PAUSE

ECHO Disable Google Play Videos
adb shell pm disable-user com.google.android.videos
PAUSE

ECHO Disable Google Photos
adb shell pm disable-user com.google.android.apps.photos
PAUSE

ECHO Disable SwiftKey
adb shell pm disable-user com.touchtype.swiftkey
adb shell pm disable-user com.swiftkey.swiftkeyconfigurator
PAUSE

ECHO Disable Facebook
adb shell pm disable-user com.facebook.appmanager
adb shell pm disable-user com.facebook.system
adb shell pm disable-user com.facebook.services
PAUSE

ECHO Disable AutoNavi
adb shell pm disable-user com.amap.android.ams
PAUSE

ECHO Disable Browser
adb shell pm disable-user com.android.browser
PAUSE

ECHO Disable E-mail
adb shell pm disable-user com.android.email
PAUSE

ECHO Disable Find my Phone
adb shell pm disable-user com.huawei.android.findmyphone
PAUSE

ECHO Disable Wallet
adb shell pm disable-user com.huawei.wallet
PAUSE

ECHO Disable Health
adb shell pm disable-user com.huawei.health
PAUSE

ECHO Disable HiBoard
adb shell pm disable-user com.huawei.intelligent
PAUSE

ECHO Disable HiPayment
adb shell pm disable-user com.huawei.android.hwpay
PAUSE

ECHO Disable HiVoice
adb shell pm disable-user com.huawei.vassistant
PAUSE

ECHO Disable Huawei IME
adb shell pm disable-user com.baidu.input_huawei
PAUSE

ECHO Disable Yellowpage
adb shell pm disable-user com.huawei.yellowpage
PAUSE

ECHO Disable SIM Toolkit
adb shell pm disable-user com.android.stk
PAUSE

ECHO Disable Smart Repair
adb shell pm disable-user com.huawei.hwdetectrepair
PAUSE

ECHO Disable SkyTone
adb shell pm disable-user com.huawei.skytone
PAUSE

ECHO Disable Android Tips
adb shell pm disable-user com.huawei.android.tips
PAUSE

ECHO Disable Weather
adb shell pm disable-user com.huawei.android.totemweatherapp
adb shell pm disable-user com.huawei.android.totemweatherwidget
adb shell pm disable-user com.huawei.android.totemweatherapp
PAUSE

ECHO Disable DayDreams
adb shell pm disable-user com.android.dreams.basic
adb shell pm disable-user com.android.dreams.phototable
PAUSE

ECHO Disable Navigation Dock
adb shell pm disable-user com.huawei.android.FloatTasks
PAUSE

ECHO Disable Digital Balance
adb shell pm disable-user com.huawei.parentcontrol
PAUSE

ECHO Disable Partner Bookmarks
adb shell pm disable-user com.android.providers.partnerbookmarks
adb shell pm disable-user com.android.partnerbrowsercustomizations.tmobile
PAUSE

ECHO List disabled packages
adb shell pm list packages -d
Pause

ECHO Re-enable HiSearch
REM adb shell pm enable com.huawei.search
PAUSE

ECHO Uninstall HiSearch
REM adb shell pm uninstall -k --user 0 com.huawei.search
PAUSE

ECHO Re-install HiSearch
REM adb shell cmd package install-existing com.huawei.search
PAUSE

Prepend corresponding lines by REM (or remove) if you want to keep FaceBook, SwiftKey, Health, etc

Of course, Developer menu and ADB debugging must be enabled (few clicks)

To find out package names for particular apps, install and use an app like AppInspector or PackageManager (from Playstore)