This is a great time to get into A&T recruiting because there are a lot of roster spots available. The sport is undergoing rapid expansion so a lot of new teams are looking to build out entire rosters. The coaches aren't expecting a ton of familiarity with the sport since there's no analog available at the high school or club level, but it's helpful to watch some meets on ESPN+ or YouTube. I know that helped my daughter a lot- she not only liked what she saw, she impressed potential coaches with her knowledge of the sport.
As for skills, it varies depending on your background. If you're coming from artistic gymnastics, they are looking primarily for tumbling. The "biggest" skill being thrown right now is normally a back 1.5, but I expect that to change over the next few years. My daughter also posted videos showing strength, like holding pikes on parallettes and handstands, along with standing tumbling. She got a lot of attention just on her instagram, and was able to snag several great offers before she committed this week.
One last tip-- if you have a child who is interested start getting in touch in the fall of junior year. The season starts in February, and if you email coaches in season you get lost. My daughter is just now hearing from a lot of schools who were her original top schools, and now she's committed. It's fine-- she's ended up where she needs to be, and we're beyond thrilled. But if she'd gotten in touch in the fall instead of waiting until season started she might have had more talks with those schools.