Seen grouse on crabapples that size. Although they'd probably prefer smaller. Also, they will pick at ones on the ground and dried up ones get smaller.
dolgo or siberian seedlings would make good crabapples. Grafted dolgo will be about the size you mentioned.
Lots of places selll smaller crabapples. Getting siberian seedling and adirondack crabapple from siaint lawrence nursery. Probably can order from them still.
Winters with decent snow, the local deer herd up by the lake. Not a footprint or trail camera pic. Snowshow hare and praire and roufed grouse are at camp year round. Doing about 1/3rd bird crabapples. Also planting mulberry, they'll be all over that tree july through early september.
I hear people talking about how birds love the ornamental crabs and it got me thinking; Assuming grouse would eat them, what kind would you plant? I've seen lots of them around me in town that are small but they are still holding fruit. I would think I would want something that actually drops them in the fall.
I've got a nearly mile long 'driveway' into my cabin and it's on the western edge of the property and not very close to where we deer hunt or where my plots are. The road had some work done on it and I'm thinking of planting it in clover and the having several crabapple trees...