A few comments here from your moderator:
The number of known tree species whose wood can safely be introduced into an aquarium are few. Those few are usually very dense woods with low sap contents. Most safe wood is wood which has been buried for years in bog conditions and which have, in some cases, been semi-"petrified".
All "green" wood is bad or at least dangerous in aquariums. Pine, +softwoods or any resinous woods a no-no. Cedar is loaded with a chemical folks throughout the ages have used to discourage insects -- the insects won't go near it. Don't even think of using it.
The epoxy thing won't work long term, but as long as the epoxy is well cured and off-gassed -- it won't do any harm. Don't worry about the gloss, it can't be noticed underwater.
One could always make or buy reproductions of such woods made entirely of epoxy or polyester. While the purist in me shutters at such a thought, if it looked very, very real -- I might just consider. the possibility -- especially if I lived where there are no good alternatives. At least it would be inert and easy to clean of algae, etc. Ditto fake rocks.
Tannins or their color can be removed with carbon.
The only "safe" wood I know of personally is Causserina equifolia, common name "Australian Pine". It is neither exclusively Australian nor a member of the Pine family, being a seaborne island hopper by way of floating seeds. It is common in many tropical and semi tropical seaside settings and it's wood is iron hard, dense and perfectly safe in aquariums.
It is found as driftwood here in Florida where seaside erosion and storms in the Caribbean and other places launch many a tree into the ocean each year. A few year of soaking in ocean brine, being tumbled by waves and bleached by the sun produces a perfect product.
Good luck!
Bobo