Thanks for testing!
When searching for the USB ID in this ticket Problem with T3 airmouse on Version 8.95.001 and beyond (RPi3 B+) - LibreELEC Forum (2389:00A8) I found this bug report: 4.18 regression: composite usb mouse/keyboard went mad — Linux Input
It suggests the problems started with kernel 4.18, which matches this description here (8.90.005 and before shipped with 4.14 on RPi, 8.90.006 switched to 4.18). Unfortunately the bug reporter didn't do a kernel bisect so it's unclear what exactly went wrong.
So unless someone with the problematic device(s) can check when/what broke and discuss that with the kernel developer disabling mouse support in Kodi is probably the best option.
so long,
Hias