long exposure Nex 6/7

New to the Nex group but thinking about getting my dad the Nex 6 or 7, few quick questions, appreciate the help.

1.) Can you do long exposures 1- 30 mins without touching the camera? (worried about movement) Doesnt look like there is a cord option? phone? remote? how do you set up a 20 min shot on a tripod without touching the camera?

2.) interchangeable batteries, does only the 7 have these? this might be a deal breaking for long trips.

3.) Has anyone used the 6/7 with the Nikon 16-35 F4? was thinking it would be a nice WA lens for landscape with MF + peaking.

4.) Can any other buttons on the 6 be programed for exposure compensation or AEL/AF lock? any difference with the 7? From what ive read the real dial doesnt do anything in Av mode? weird..

appreciate the help,