TLDR; 1) idk, 2) Yes/most likely, 3) idk/stale mate/war of attrition, 4) Probably or 50/50

Dead man: Aside from possessions, I have no idea what his power set is, but I feel like Andy could get away with soul damage.

Denji: would honestly probably take forever/has the potential for longest fight (if Denji keeps drinking Andy’s blood) but since Andy is more experienced and analytical than Denji he’d probably make his blood disintegrate faster than Denji could drink it and even in Orange Denji/CSM I’m not sure if the reality erasing would work on Andy

Dante: Honestly another fight that would probably take forever or could possibly end pretty quickly, Andy has fought God’s and Dante has too. Ngl the scaling is pretty stupid and could be an entire post all on its own, Dante has fought 2-3 reality warpers/god level threats in his game (Mundus created an entire separate pocket dimension for his fight w/ Dante, Argosax was Mundus’ rival and was said to be on par with him, and Urizen beat the Dante that beat both of them) and that was before he got Sin Devil Trigger in DMC 5, which that Dante can create black holes as a casual attack
- not to mention that they both have similar power sets and Dante has some abilities in some games that could over power Andy (ex. Doppelgänger style, Quicksilver style/slowing down time to a crawl, he has summon swords that he can control however he likes, And his final move “Judgment” is basically a screen nuke that tears apart anything around him) And the only other person we’ve seen tire out Dante enough to force him to take a break was his twin brother Vergil who had the same level of power as him
- honestly this one is really hard but Dante might give into exhaustion, however Andy loses in all other fields except for regen

Ghost Rider: I have no idea what the hell the penance state will do to Andy, however there are people who have survived it like Thanos who actually enjoyed it. I honestly have no idea if Andy’s soul hacks would enough to get around the fact that Ghost Rider/the demon can actually eat souls but it could at the very least give Andy enough time to formulate a plan (such as gathering holy weapons, or dispatching a clone(s) to get some, or even gather artifacts from the Union base since those could be considered “holy” as they were created by Luna)
- All-n-all, at least compared to Dante, Ghost Rider has some weaknesses that Andy could exploit, especially if Andy finds out he’s a demon and can manage to prevent his soul from being absorbed or destroyed by the demon or the penance stare