I’m about to do a couple projects that will involve chamfered and/or roundover edges on 3/4" plywood. I want smooth, consistent edges on them. It’s OK if the ply layers are visible; in fact, visible layers will add to the aesthetic of a stained desktop / work surface, but smooth/sealed edges will be important as the intended use includes resting hands/wrists on the edges.
I’m using high quality birch plywood, so I don’t expect significant amounts of voids/knots, but if they are there I obviously want to fill them in.
In the past, I’ve actually had good luck just smearing on Titebond glue so that it fills and soaks in a bit, then sanding it down. Only really looks good if the edge is painted with an opaque color, though.