The plugs are usually cut on the drill press.......Cut only partway thru the donor board......then they're snapped off with a chisel or sawn off the board by slicing it on the table saw........cutting from a thin board requires individually removing each plug as it's cut.....
I like a Pilot/counterbore instead of the forstner bit........the built in stop and pilot/clearance holes make this job much simpler...........
and even tho you've pre-sanded......use the glue and sand the plugs
All the same sized 8' boards ? That makes for a busy joint/layout pattern