MDO ply is plywood with paper faces fused on and is commonly used for outdoor signs and such. It comes in Medium Density Overlay one side or both sides 1/4", 3/8"/1/2", 3/4". It also comes in Heavy Duty Overlay and not sure about light duty...

I've seen boatbuilders use it for deck and cabin flat surface forms in plug making.

You can glue with epoxy to the paper with some success but I prefer the greater success of the glue joint in removing the paper for glueing or 'glassing. I've used it for years for bulkheads for my little boats, bunk fronts, and countertops that will be painted. In the pic, all those are MDO ply in a boat I launched in 1980. After thirty some years and severe neglect by subsequent owners and a major rebuild by a new owner recently, all thos parts amid the ruin were still solid and looked good.

Counter tops that are in this case covered with nasty contact cement and the formica are MDO faced undersides with no paper tops due to the formica.

It can make a nice face ply lamination on thicker bulkheads with a paper face out and no face on the lamination side. Super smooth surface, piece of cake to paint, maintenance free, as it were. As with all plywoods the edges must be sealed, preferably with epoxy, to prevent moisture issues.

Usual disclaimers. I own no plywood stocks nor work...well, at all. Retirement is wonderful.