Mover adds in ".partial" during the move to solve various problems that users have on occasion
This makes your filename too long. Right now, your source is 255 characters on the filename itself. This is the maximum length of any filename.
I'd simplify your naming convention that you've got (presumably) sonarr naming the file to. It seems to be a tad much, having both the [S01E12] and the episode # 012 separate, along with all of the file info x264, audio etc in the filename itself when usually it only needs to be done in the associated .nfo file unless you want to see at a glance everything about the file.