FtMs / trans-identifying females (to borrow the TERFs term) are women on steroids. It's really not fair to have them competing against women, since they are on steroids. From what I'm aware of, they aren't really competitive with actual men, because despite being on steroids they are women, but IMO there's still really no way they can compete fairly.
My understanding is that trans-identifying females taking the more common amount and types of steroids are not competitive with men. If more powerful steroids were developed and became standard practice for trans-identifying females, then it would seem possible that women on steroids to at least be competitive with men.
There can be no "correct" or "fair" level of steroid use, or a well-defined level that makes a woman as strong as she would have been had she been born a man, because the question is fundamentally a non sequitur, a man born in her place would have been a different person, with different genetics and would have developed along different lines.