There are apps/games you can play to compare kinks/desires. I’m rubbish at remembering the names, but I’m sure there’s a post in the forum I could dig out. 
I think there’s one you both fill in separately, and then it only shows you just the things you’ve matched on. That way you can be honest without worrying about revealing too much.
I’ll have a little root around.
I found this old thread with a few in, as well as a link to a LH blog about some.