Porky's time travelling is REALLY weird
Something that I find very creepy in Earthbound is that Porky probably is a zombie at the final battle with Giygas.
Mr. Andonuts specifically said that physical bodies can't time travel so...what happened to Porky when we fight Giygas? Could his spider mech keep his body somewhat intact?
I mean, now that I think about it, he could definitely have time travelled just by being in his spider mech, so why would he need the Mr Saturn's machine?
If he needed the Mr Saturn's machine, then he probably time travelled first and then had his spider mech in the past, but that means his body wouldn't have been abled to survive the first time travel...creepy
TLDR: Porky most likely didn't survive time travelling with Giygas to the past and is now an immortal zombie
(If Porky's "dead", then maybe that could also explain his blue skin, other than Giygas' influence)