Ustadh if my female cousin is getting nikah done in the masjid and there is men and women but they sit on opposite sides with no barrier, and the nikah is done infront of everyone (no hijab). is it I sit permissible for me to attend and just stick to the men and avoid mixing as much as i can

Ustadh AbdulAziz al-Haqqan

How freemixing or women without proper hijab inside the masjid!? Is this what u mean?