re: "If there is a way, does it also work for basic props?"

Yes.

You can "glue" them together.

Export all the objects you want to have as a single object to a Wavefront OBJect... file.

Then, Import that file back into Poser and it will be a single object.

If you have group data for the objects, make sure to check "Include Group ..." when you Export ...
... or you will lose that information.

If you want to keep the same size (scale) ...
... make sure to UNcheck the "Percent of Figure size" when you Import the file back into Poser.

cheers,
dr geep
;=]

Remember ... "With Poser, all things are possible, and poseable!"

cheers,

dr geep ... :o]

edited 10/5/2019