See the edit, it's plastic surgery in general. But major plastic surgery would include change in genitalia - due to several factors including time. Getting botox (something I don't find attractive) is something I would consider minor.
You don't need to be able to tell to not like it. Looking good does not necessarily equate to attraction.
Considering I've not really met a transgender, the only one I've seen was early on in transitioning so for aesthetic reasons I'm not going to include that. Maybe I haven't thought about it because I haven't seen the reason for it, hasn't affected me yet, or simply don't care about it either way.