Ultron (MCU) was trying to help humanity evolve while Infinity Ultron sought to eradicate all life.

I'd say Demona from Disney's Gargoyles. I mean, there was that one episode where she traveled back in time and her past self met her future self.

Dr. Doofenshmirtz 2nd dimension

Oh, yeah. Although I much prefer the original Dr. Doofenshmirtz, mostly because Alternate Doofenshmirtz as I like to call him tried to kill him along with Phineas and Ferb. That was not cool.