To epoxy or to spar varnish?

My son has posed a dilemma for me. He’s seen all kinds of vegetation epoxied into the tops of tables, and has decided that’s what he wants to do with green leaves. Problem is, most everything I’ve seen is recessed into voids or has had an area routed out to accommodate the vegetation. He wants a “bas relief” where the leaf rests on top of the piece and is either dipped into the finish or has the finish brushed on. The pieces we’ll be using are like the one pictured below.

The sizes of these slabs will vary from 8” up to 18”.

My question is whether or not anybody has had experience “dipping” green vegetation into the types of finishes I’m considering, and, if so, what your results were. If anyone has any suggestions on how I might go about doing this, it would also be very much appreciated.

Thanks.
TZH

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