Today 10 bits are available for a small number of devices that support Hevc Main10Hdr10. These are Sony Xperia 1/5 / 1II / 5II, LG from V35, Samsung S10 / S20 (Snapdragon), Xiaomi Mi9 / Mi9T / Mi9 Pro / Mi9T Pro (but only Rec709). Perhaps there are others, but now it is difficult to remember them all. Also 10 bits video recording can be limited to 3840x2160 resolution.
We
observed that on Mi9T and other Xiaomi devices with a processor lower
than Snapdragon 855 10 bits are available only up to 10 Android. More
often on the 9th.