It's really all about context.

If a woman is walking into a social event, dressed to the nines, then an in-person complement about how she is dressed is appropriate. And this would be true even for me--I am not exactly a 10, but I clean up well. Tell me that I look great. You would probably do the same for one of your bros.

In a professional setting...absolute no. No. Just no.

In the absence of context, such as the post in question--probably best not to post in the first place, unless it is mid-season, and she just had a career-best game. And don't mention her appearance, just her performance.

"Man, I am glad that we admitted women to ND. Player X just went off for 28 points, including 5 for 8 from the 3 point line, and hit the game-winner with 6 seconds left. Great game!! Go Irish!!"