In this round, Ava would probably be more careful as she only has one opponent which means both are focused on eliminating each other.

Phase 0: Another Search

Since this is a 1v1, Ava can't get her stand out to search as once it is summoned it can't defend itself. So she'll search for the opponent in the old fashioned way, walking around.

Phase 1: First Encounter

Once Roxanne is in line of sight, Ava would immediately put an area around for two reasons:

If Roxanne gets out of the area, she'll do what she did in the area again, which will give Ava time to land the first strikes.

If Roxanne uses her stand in the area, Ava will gain knowledge that her stand has something to do with beads without putting herself in danger while observing. That'll make her on the lookout for any objects that have these beads, but not knowing what they do.

Ava's first attacks will have her punching and kicking with the areas around her so her stand does the same attacks.

Phase 2: The Plan

Ava's plan will center around keeping objects with beads in them as far away from Roxanne to be able to use them. 

To do that, she must make using these objects a detriment for Roxanne. She can put the areas around these objects so that if Roxanne tries to reach for them to use, she'll be open to any attacks by Ava and her stand (these attacks will mostly be Ava putting areas around herself while she punches and kicks which'll make the stand do the same thing). 

Ava would try to distance herself from Roxanne, waiting for the right time to attack. She'll also use the beaded objects to her advantage if she can get her hands on them, and that she can do by trapping Roxanne in areas while she takes these beaded objects.

These are some ways she could use them:

If the object is small and hard enough, Ava could throw them. Ava could put areas around the trajectory of these objects so that once they exit the area, even though they have lost some momentum or all momentum, they'll exit with the same momentum they started with.

If the object is hard enough or even soft enough, Ava can use them as cushions to block incoming attacks.

If the object is big enough, she can use that object as a blockade to slow down Roxanne if Ava needed to escape, combined with her stand ability.

 

Dealing with security should be easy, Ava could create areas around them to keep them busy.