Multiple phones in the same household?

How do I configure my plex pass so that both mine and my wife can have our phones sync pictures to our Plex server? Do I just log in as me on her phone or do we have to have 2 plex accounts?

You can log in from her phone with your account. If you want to separate ratings / if a video has been seen etc., you can activate Plex Home and create a 2nd (managed) user for her.
https://support.plex.tv/hc/en-us/articles/203948776-Managed-Users