not exactly a bug, but the sound cue on viscous' puddle punch makes it seem as though you can parry it much later than you actually can, making it very frustrating when mistiming parries. this may be due to latency or server lag however rather than the actual sound queue of puddle punch.
Game incorrectly says you must sell an item to buy a double component even if you have the first item ( e.g. extra spirit into boundless spirit). Still able to buy improved spirit and then boundless without no issue.