Feel free to elaborate.

I’ve had no problem for years.

Biggest issue I’ve had was forgetting I committed something on one device before committing on another. Then I had two branches where one had " conflict" in the name. I just deleted all conflict files and everything continued as normal. If your repo is never corrupted before syncing worst case you should be able to find and delete all conflict files.

Syncthing conflicts include the source of the conflict so you could just choose to delete all files whose conflict is from one device and leave everything from the other.

If you’re worried you could just ignore your ‘.git’ folder in syncthing since you’re purposefully not committing during this. Then sync through git when you finally commit your changes on a device.

If only there was some syncing thing that would let you move arbitrary files between devices.

https://github.com/syncthing

GrapheneOS has had better compatibility with sanboxed google services for a while now. Microg is worse.

Did you measure that empirically? Gsam indicates it only accounts around 1% of battery drain.