hello and welcome to the forum,
if you copy a file direct to onedrive, not using the rclone mount
then, by default, there is a five minute delay before rclone will notice it.
https://rclone.org/commands/rclone_mount/#vfs-directory-cache
"changes made directly on the cloud storage by the web interface or a different copy of rclone will only be picked up once the directory cache expires"
and in the forum, there are number of posts about inotifywait, did none of those answer all your questions?