Both yellow bean and black bean sauce are made with a type of soya bean, so depending what you are cooking black bean sauce could be a an alternative. Read somewhere that hoisin could be used, but is much sweeter.
you can use miso paste, it's also a fermented bean paste like yellow bean paste. I would use less as it's quite salty. I was only able to find yellow bean paste at my oriental grocer. Would share it with you if I could! It's tasty stuff, added some to a stirfry the other day and it was scrummy.