Suggested by iKnowledge Sebastian Shaw is a tough fighter who absorbs kinetic energy. If Batman only had his normal form then I think it’s very safe to say that he would lose this battle. I don’t think the gadgets would be enough to stop him. Batman has obtained tons of super forms over the years though that really give him a way to fight back like when he got Superman’s powers. Shaw’s not going to be able to stop him and will ultimately go down here. Batman wins.
If Sebastian Shaw can use all he has: https://marvel.fandom.com/wiki/Sebastian_Shaw_(Earth-616)#Powers_and_Abilities, then regular Batman is defeated. If Batman truly gets all his powers and gadgets at their highest, then he has a chance. It would be a battle for the century.
I agree, regular Batman would lose this fight. He just doesn’t have anything that could put Shaw down