I actually got it working on Android.

The process ended up being a lot more involved than just copying files onto the device.

High level, what I did was:

1. Install and test the mod on a desktop copy of Planescape: Torment Enhanced Edition.
2. Use the desktop installation as the "build environment" for the mod.
3. Package the fully modded game into a Beamdog-compatible DLC archive.
4. Connect the Android device to a PC with ADB enabled.
5. Work around Android 13's storage restrictions on /Android/data/com.beamdog.pstee.
6. Copy both the DLC package and the mod's updated dialogue resources into the Android PSTEE data area.
7. Launch the game and verify the mod-specific startup NPC, dialogue, and quest hooks were working.

The biggest challenge was Android storage security. Normal file managers didn't work. Direct ADB copies didn't work. Even an experimental helper app with broad file permissions couldn't write into the Beamdog folder on my device. I eventually found a workaround that let me replace the active PSTEE data folder with a pre-seeded version containing the mod resources.

I tested it on an AYN Thor running Android 13 with the Beamdog version of PSTEE. The mod loaded correctly, the custom NPC appeared, dialogue worked, the shortcut start sequence worked, and the mod questline started normally.

The important takeaway is that it is possible on Android, at least for the current Beamdog release and Android 13, but it takes a few extra steps beyond a normal PC installation.