Looks like a lot of effort went into this, shame about the softlock but I can at least give honest feedback about the first part!
The sprites are well made and aesthetically pleasing, the level design is interesting and fun - I particularly liked that the “reversal” included literally traversing the first level backward as the other character, was hoping that might be a recurring thing later! - and although I have to say that M is definitely an odd choice for the attack button imo, it was suitably challenging to actually defeat enemies and time movement with attacking, when combat was necessary to continue.
Very well done in spite of the softlock bug, would love to see this get updated at some point in the future to fix and see how it ends! Saving it for later. 😎👍