Your question is going to be moved down to the Props section. But each manufacturer has it's own propshaft and prop configurations. Mercury makes props with hub kits adaptable to most. It depends a lot of horsepower. Wutcha got?
Rubber-hubbed Merc props will fit, but you need to fabricate some hardware. Plastic hubbed Merc props will fit and you can get a Yamaha hub kit for it.