Depends on the GSI rom. Some have microG, some have play services, some have none, some come with debug variables enabled.
In my understanding, GSI roms (project treble) are like a shell around the main android components, like firmware, so they are generic to every device, but some features might break. Here are some ROMs.
There are some details, like vndk and vndk lite, A/B partitioning, if the ROM is signed, etc.
Depends on the version, if it's android 15, use GSIs with android 15 or higher, with versions equal or higher than the vndk on your device, then it will work.
One example to the naming is in the Andy Yan's LineageOS build:
https://sourceforge.net/projects/andyyan-gsi/files/lineage-21-pre-qpr2-light/
With attention to the naming scheme, I think you can grab any that has the features you want. Oh, and microG now has a build that doesn't need signature spoofing now, seems android doesn't check the signatures on system apps agains the binary data, so just copying it to microG solved (from what I understood).