First, I would suggest to stop "persuading" him to do anything...you can suggest (once), but after that it can be seen (by him) as a threat to the relationship.
"If I don't "be the girl", The Thing might leave me!"
"If I don't take hormones, The Thing might leave me!"
Etc.
If you're concerned about his manhood, you can ask if he wants to go back to his original body...if he says yes or no, accept it as his answer.
Now having said that...if there's no controlling or abuse issues, I wouldn't think a man would take hormones simply to please another person, because it affects so much--as you noted, his skin is softer, breasts, different perspective, etc. If you don't have these issues, you did not trigger his transition. He is responsible for his choices. This suggests to me that he is trans...but as you've read already, there's an entire spectrum of variables and outcomes.
Ask your partner what he wants (and find out what pronouns--he, she, ze, ihr--are preferred).
And a question for you: if your partner continues with hormones, would you be comfortable with that? How about dressing as a woman outside the bedroom, to the store, football, etc? Would any of that change for you?
Good luck with this, hoping for the best!