YTA You're going to have to suck it up, and it's going to get worse. 8 week old diapers smell like freaking roses compared to a two year old eating solid food and producing the most vile shit you could think of. Never mind accidents while potty training where it isn't confined to a diaper, it's all over the place.

Children are tornadoes of crap, piss and puke for the first few years.

You say you can do it if alone but don't want it to be a primary responsibility. Is your wife asking that you do all diaper changes as a primary responsibility or do you mean that you just don't want to do it when you can pass the buck? If you do it while alone with her, you can do it. You just prefer not to. Welcome to being a parent, get over it.