Wonder woman doesnt figth using speed like Flash does. And neither does Superman or Captain Marvel. Now *that* is silly.
Flash isent a brick. He is a speedster. Everything he does its about speed. He is a character built to figth like that. Wonder and co, are flying bricks. They have high speeds, but never pull out nonsense like "hitting someone 1000 times before they blink". Thats fangasm talk.
Especially when the opponent isent slow either. You are aware that Hercules for a brick can pull good speedburst moves, rigth? Cool.
The one reason he wins in a ring more often, its because it works more at his advantages. A ring is a limited area, so her fligh wont matter much. Hes got the considerable size advantage. He is usually more brutal at using his skill than Wonder Woman is, her standart speed advantage isent usually so big against slower bricks than she can just steal a win that way. Hercules is also usually more durable than she is, and arguably stronger.
Heck, even if you think she is stronger, the gap is so small, that in a limited area he still got the size advantage.