Check out my unofficial guide here #・tips-and-tricks message - tested on MacBook Air M2 with latest macOS 15 (not tested on macOS 26 beta, but no reason to believe it won't work)
It's based around a modernized version of how Spore used to work on Mac back when it was officially supported, so even though this is no longer officially supported by EA and requires some third-party tools to get working, the game was pretty much designed to work this way
I wrote it for GOG as it's the easiest to get working due to no DRM or required launcher - it is currently 75% off so I would recommend that way https://www.gog.com/game/spore_collection
In theory it may be possible to first install EA app in the bottle and then install spore from there, but I have no idea if this would work as well, or even work at all