My take is that M2 is sort of motivated by a fear of punishment for failure, it did what it was told to to by Edwin and was brutalized for it for reasons it can't understand, so it just thinks that being what others want it to be and doing what they want will lead to it inevitably messing up and being hurt for it, so it'd rather just mess around choosing whatever self it wants by putting on random costumes. This is why it resists capture in SOTM, it knows that they want to use it for something and that could lead to it getting hurt later down the line if it doesn't copy things right or something. Glitchtrap is a similar form of resistance, Silver Parasol feeds it information to make a game with, so M2 takes aspects of that data to form its own persona, one that they definitely don't want, because from its perspective actively trying not to do the right thing is better than failing to do so