you had been; you would have been
I wish you had been there.
No sabía que lo hubieras estado.
I didn't know you had been.
— Los Tenenbaums. Una familia de genios (2001)
Desearía que hubieras estado ahí.
I wish you had been there.
Si hubieras estado atento, esto no hubiera pasado.
If you had been paying attention, this wouldn’t have happened.