If you create another trait or segment with exact same logic, AAM will not let you create another and suggest you to use existing, as there is a limit on number of traits and segments you create.
To cope that, I would create the app visitor trait with the default expiry of 120 days or 0 days so it never expires.
Then I would create two segments:
Segment 1: Using app visitor trait only without any recency and frequency setting.
Segment 2: Activity trait (search with All Active Visitors) AND "app visitor trait" with recency <= 14 days and frequency => 1.
Thanks,
Varun Kalra