No, not available on Mac. The expression is fine, there's no syntax error. It's possible that the forward slashes cause some problem in the Rename&Copy tool in Mac though, it may be a bug. Did you try adding the expression as an Expression column in a Details view? See the screenshot below. If it works as an Expression Column but not on the rename tool, then it's a limitation/bug due to the fwd-slashes, which are also the escape character in an expression. We can try not using the fwd-slash:
[Album Artist (auto)]//replace(trim(replace(replace([Album],char(91)Lossychar(93),),char(91)Incompletechar(93),)) char(40)FieldQuery(Album Artist char(40)autochar(41),[Album Artist (auto)],Catalog #,1,0)char(41),char(32)char(40)char(41),)
That's the same as this one, but using no slashes (except the one after [Album Artist (auto)] to create a subfolder):
[Album Artist (auto)]//replace(trim(replace(replace([Album],/[Lossy/],),/[Incomplete/],)) /(FieldQuery(Album Artist /(auto/),[Album Artist (auto)],Catalog #,1,0)/),/ /(/),)
You can also try a single slash as the path divider:
[Album Artist (auto)]/replace(trim(replace(replace([Album],char(91)Lossychar(93),),char(91)Incompletechar(93),)) char(40)FieldQuery(Album Artist char(40)autochar(41),[Album Artist (auto)],Catalog #,1,0)char(41),char(32)char(40)char(41),)