For years, fans begged EA for backwards compatibility on Xbox One and Series X. While Fight Night Round 3 is playable via BC, Champion remains stuck in the past due to music licenses (the game features a killer soundtrack from The Hives to El-P) and boxer likenesses (including the estate of Joe Frazier).
Many players look for an to use with emulators like Xenia . While emulation itself is generally legal, the acquisition of ROMs exists in a legal gray area: Xbox 360 Fight Night Champion Rom
The game is technically not "abandonware." Even though EA no longer sells the game on the Xbox Marketplace (it was delisted years ago due to licensing expirations for boxers like Mike Tyson), the copyright is still owned by EA Sports. They could theoretically release a remaster tomorrow if they paid for the licenses. For years, fans begged EA for backwards compatibility