He would be decimated, and worse for him, it would cost him some of that nutjob base he has in those insecure men whose worst fear is a strongman banging their wife and getting 'cucked'. Just imagine it, poor Trump up there getting grilled and taken to task on his lies, flip flops, inexperience, lack of intelligence.. by a woman. Those insecure male supporters would have a meltdown.
Trump is in big trouble when those debates roll around. He's told so many lies, flip flopped on so many issues and lacks experience and intelligence that he's going to be a real easy target. This will not be like running for the nomination of the Republican party, where he can just make silly faces, throw his hands around and call everyone names. That only works on that base, he's not going to win over the people who will not vote for him right now with that vapid nonsense.
He'll probably bring up conspiracy theories and personal attacks against her. But when it comes to the real issues, which will be unavoidable for him in these debates, he'll be decimated. Crazy talk like banning abortions and punishing woman who have them, banning a religious group, leaving NATO. He doesn't even understand these issues, much less have a footing to defend his crazy talk on them.
It's going to be gold entertainment. This whole shit show has been hilarious and the likely culmination of seeing this imbecile trying to make a concession speech when he loses... I doubt he'll be able to do it. He's going to sue someone and claim it was all rigged. As much as I pity everyone living there under the horrific possibility, however slim, of having this moron be their country's leader - it has been the best entertainment. When you see him being interviewed or talking and it hits home just how fucking idiotic and out of his league he is for what he's running for, it's comedic gold. He's a complete embarrassment, it's going to take decades to live down the joke.