Pyron is not a sun, he's a Cosmic Fire Elemental. Donavan beat Jedah Dohma, who absorbs dimensions in his right hand, is a half-vampire, and has a sword that has three Gods in it that add to his power. Comic Pyron was completely based on the OVA one, they can do the same thing, and also they all have the same abilities as game Pyron, so all 3 sources are eligible. Finally, I'm pretty sure the fights in the OVA were slowed.
In the OVA Donovan was not anywhere near Superman levels.
Even though the comic and the OVA may share similar characters, they are still not one and the same, similar to cartoon Supes vs comic Supes. Same character with same abilities, but they can't be interchanged. Pyron had no attacks that could hurt Clark based on the OVA.
I love Darkstalkers, but I don't see the OVA version of Pyron winning...especially against Superman Prime.
Comic may be different vs standard Supes...but like I mentioned..I'm not familiar with it.