Yes, you can continue playing on Mac by logging in with the same Steam account.
inZOI purchased on Steam shares its license between Windows and macOS, so you can run it on Mac without any additional purchase by logging into Steam for Mac with the same account.
* Will my save files carry over as well?
Save files are not automatically shared between the Steam and App Store versions.
However, you can manually copy your save files to continue your progress.
Can I continue playing inZOI on Mac even if I’ve been playing it on Steam(PC)?
Updated
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