Yes, that is actually intentional. When working on low-res sprites I just mirror the left/right frames to save time and to preserve visual clarity. It's something most pixel art games do (even big ones like Megaman, Castlevania, Prince of Persia, Blasphemous..). Otherwise you'd spend a lot more development time working on each frame that has the character wielding or swinging a weapon, and those details are usually overlooked while playing, so it's not worth it.
Anyway, I'm afraid I don't plan on changing that at the moment, but thanks for asking :)