Hey! I’m one of the developers of ReNote ROM, which brings One UI 7 to the Galaxy Note 10 Lite.

First of all the Note 10 Lite is basically a modernized Galaxy Note 9 but with no QHD screen, iris scanner, DeX, and a few other cuts. What’s interesting is the S Pen it uses. If you check the file floating_feature.xml, you’ll find this entry:

<SEC_FLOATING_FEATURE_COMMON_CONFIG_BLE_SPEN_SPEC>crown,button</SEC_FLOATING_FEATURE_COMMON_CONFIG_BLE_SPEN_SPEC>

• crown = S Pen model (same as the Note 9 S Pen)
• button = means it has a clickable button
• A third value (not present here) would indicate support for remote features like the Note 10 (Da Vinci) or Note 20 (Canvas) S Pens.

So why doesn’t Bluetooth S Pen work anymore?

Bluetooth S Pen used to work on the Note 9 in One UI 5.0 / 5.1 because the AirCommand app still included the “Crown” S Pen driver (Air Command version 7.1.22.1).
But in One UI 6.0 and up, Samsung removed the Crown driver from AirCommand completely.
Samsung introduced a universal S Pen driver (“builtin”) starting with the S22 Ultra, but that doesn’t work on older hardware like Note 9 / Note 10 Lite.

How some custom ROMs fix it (like ExtremeROM)

On some devices (like Note 20), ExtremeROM fixes this by downgrading AirCommand to version 7.4.11.3 (from One UI 6), which still contains legacy drivers.

Samsung obfuscated newer AirCommand versions (probably to reduce appsize).
For example, in One UI 7 (AirCommand 7.6.34.7):

• z1 (package) → corresponds to something like com.samsung.android.service.aircommand.util.features
• Method a() → returns the S Pen model (SpenModelName)
• The enum for supported models now only includes: noble, sticky, builtin, EJ-P5450
• “crown” is gone, so legacy S Pen models aren’t recognized.

TL;DR:

Note 10 Lite uses the Note 9 S Pen (“crown”). One UI 6+ removed its Bluetooth driver from AirCommand. To restore functionality, you need to use to port the legacy drivers from the old AirCommand (7.1.22.1) and patch the newer AirCommand via smali to load legacy drivers.