@vpilotfs @Merlin664554 and OMFan13009
Found out it might be even easier:
Close SimAppPro->
Go to …\AppData\Roaming\SimAppPro\ShakeEffect\effect\MSFS2020 → Backup and delete the VibrationEffect_V1.5.js file.
Starting SAP will automatically create the file again. Check if that’ll lead to success.
Otherwise just let me know.