Portable Data File for Mac?
Does QuickBooks for Mac let you make a Portable Data File?
Does QuickBooks for Mac let you make a Portable Data File?

No.
You can, however, do a Backup for Windows to then Restore on a Windows copy of QB (same year product recommended). You can then reverse the process.
Be advised that some things don't tend to make it through the round-trip.
Hi,
Can you tell the "Things" that don't tend to make it through the round trip?
I have no experience doing the roundtrip; I always printed detailed reports for my accountant.
There are many threads, most about Win to Mac or Mac to PC that describe problems people have had. Many of those are caused by existing problems with people's company files, but a few describe real issues with the transfer process.
Others here will have a better handle on things about which one must be careful.