Hiii, I've made a video about the game and wanted to share some feedback with you :D hopefully it's helpful to you :)
-The main concept of moving the characters at the same time is pretty interesting.-The gameplay mechanics could be more polished as sometimes they feel glitchy, especially while attacking.
-The visual style fits perfectly the game, but if I had to say something about it I'll say that the "health" and "energy" potions could be improved.
-I've found some bugs at the "ghosts" level, the character can't be moved correctly as you can't see where to jump.
-I also found that while you talk to NPCs the lower character can still be moved while the upper one stills talking/not moving.
In conclusion, the idea is great and I hope you keep working on it. Hopefully this is useful to you :D, also if you could subscribe that would help me a lot :)
Regards