If it's straight up power vs power, then a PISless Jack of Hearts should win (better energy output and he has that "hi tech computer" brain [that a LOT of writers keep forgetting about but it did make an appearance in Avengers : Infinity] that helps him process information/data/etc.. at super speeds [compared to humans] which should help him on the battlefield).
If SS gets creative and starts putting force bubbles in his body and then rapidly expands them, then he could win.
I like Jack so I'm voting for him but SS is awesome and I could see it going the other way too.
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..even the outer hells are indifferent matters for they bow only to potent and archaic Nodens.