Alright, I am guessing that Jupiter's devil fruit power is probably going to be a gassed up Mongolian death worm with a design that will look like a tribute to the Sand Worms from Frank Herbert's Dune.
As for how Jupiter comes back from that Giant attack, he could have a power similar to the Lambton Worm from an old English legend. A bit of an obscure story outside of Britain but then Oda knows about stuff like Finnish wind knots.
https://en.m.wikipedia.org/wiki/Lambton_Worm#:~:text=6 External links-,The legend,been terrorising the local villages
This big beastie's main gimmick was that if any chunks of its flesh were hacked off then it could simply reattach the pieces. Long story short, the hero of the tale gets advised by a witch to cover his armour in blades or spearheads so the worm cannot coil around him and to fight it in the River Wear so that the hacked off chunks of flesh drift away downriver before the beast has the chance to reattach them.
TL;DR Oda probably likes mythical worms.
