kid,

Might be stepping on my old withered air hose here, but as far as I know, epoxy primer is another name for 2k primer. This is a catalyzed primer meaning there is a part A and part B, which when mixed together harden through a chemical process.

The primer I use is quite heavy bodied and will cover a multitude of sins...I am under the impression that it is impervious to anything and can be treated as a final coat if desired.

I am not a professional painter, this is
information I have gleaned from the friendly folks at my automotive paint store...and I use these products and procedures myself.

Stuart