Might depend on controller model.

I am currently running a osmc rpi3b+ setup and the 1914 (Latest 2020 Model) with the latest firmware (5.5. something) and was running into the following issues:

Bluetooth pairing problems "connect/disconnect" probably due to BLE handling issues as far as key exchanges are concerned: can be worked around by pairing the controller with e.g. a windows device and then copying over the keys manually to the rpi (some relevant info can be found here https://github.com/atar-axis/xpadneo/issues/259). Might get better with update to kernel 5 somewhere in December/January IIRC osmcs planned release schedules correctly.

Fixing that using xpadneo drivers the controller works fine within confines of osmc (i.e. kodi interface, software running on the pi) but steam link has one major issue:

It recognizes the controller as an Xinput device and appears to load one of it's own drivers for it (the controller "works" within steamlink even with xpadneo uninstalled). Issue with that "driver" is that it overlays some hyper sensitive "mouse cursor" functionality on the left analog stick. Haven't found a way to work around this yet. This makes playing anything that requires the left analog stick impossible.

From what I have seen the 1708 model on older firmware revisions (4.4. something) seems to have had similar issues.

Using the non-bluetooth versions (i.e. those with microsofts own connection dongle) seemed to work. Take this with a grain of salt, since I'm only infering that from what I have read on the net. Haven't had the opportunity to try it out myself, yet.