To be honest, who wins depends on what rules you follow here. If by pokemon rules, then Fire is SE vs Steel, Giving MCY the advantage here. If by Digimon rules, they'd both be considered part of the Dragon family, despite Charizard's technicalities, so WGM's Dramon Killers would give him the advantage.
Basically, they both win in their respective universes. On neutral ground, I'd argue they'd be evenly matched.