I guess I'm not sure what you mean by "fork".

By fork I mean, up to the point of duplication you have Maia. After the point of duplication you have Maia1 and Maia2, both of whom are Maia, but neither of whom are each other.

If the legal identity were the same, and Maia2 were to commit murder immediately after being made, should Maia1 be punished?

Did Maia, prior to duplication, intend the murder? If so, as both Maia1 and Maia2 are Maia, they're both guilty of planning the murder. Only Maia2 committed it, but Maia1 planned it just the same.

If Maia2 were to kill Maia1 immediately after creation, then is it just passing the baton so to speak? Would it just be Maia1 creating Maia2 with the intent of suicide?

Maia1 didn't exist seperately until Maia2 was created. There was Maia, who is the past of Maia1 and Maia2