Did you ever get it to work? I think I'm experiencing the same problem you had.
The problem: Wiimotes disonnect when stopping a game, and every time a game is started they must be re-synced by pressing the sync button on the wiimote AND the sync button in Dolphin GUI.
My environment: Linux (Ubuntu 20.04), Dolphin 5.0-12286, Wii BT module that I soldered to a USB cable, bluetooth passthrough enabled.
Suggestions I tried: toggling vsync, toggling fullscreen/windowed mode, delete SYSCONF file, fix NAND, load entirely fresh NAND, use different video backend (vulkan). Unfortunately none of the suggestions fixed the problem.
Although, it's worth noting that if I manually turn off the wiimote while the game is running (by holding down the power button on the wiimote for a few seconds) and then turn the wiimote back on by pressing any button, it reconnects just fine and I don't have to re-sync. But as soon as I quit the game and then restart it or begin playing a different game, the wiimotes must be re-synced.
The problem: Wiimotes disonnect when stopping a game, and every time a game is started they must be re-synced by pressing the sync button on the wiimote AND the sync button in Dolphin GUI.
My environment: Linux (Ubuntu 20.04), Dolphin 5.0-12286, Wii BT module that I soldered to a USB cable, bluetooth passthrough enabled.
Suggestions I tried: toggling vsync, toggling fullscreen/windowed mode, delete SYSCONF file, fix NAND, load entirely fresh NAND, use different video backend (vulkan). Unfortunately none of the suggestions fixed the problem.
Although, it's worth noting that if I manually turn off the wiimote while the game is running (by holding down the power button on the wiimote for a few seconds) and then turn the wiimote back on by pressing any button, it reconnects just fine and I don't have to re-sync. But as soon as I quit the game and then restart it or begin playing a different game, the wiimotes must be re-synced.