I just sold my two jailbroken ATVs but I'm not sure what I should do to erase any of my own personal info.
If I do a restore will it erase the jailbreak? They're both untethered.
Is there anything else to do?
Yes a restore will wipeout/break the jailbreak
I would just clear all personal log ins, log out of any services if you do not have VALID shsh blobs saved to do a restore and to re-jailbreak
Not all shsh blobs saved by cydia are good... so be sure they are valid before you start https://forums.macrumors.com/threads/1650467/