Will other trackers, such as those from Samsung, fit in the AirTag compartment?

No, only Apple AirTags fit perfectly into the designated compartment in our wallets.

Of course, we don’t know every model available on the market.
However, if they are larger and/or thicker, they won’t fit. Trackers of the same design or slightly smaller ones can certainly be accommodated, but you may need to try them out to be sure.