im thinking about rushing my second account for some socket quest,,,
but i would try to premap them first,,, and maybee sell spot at 5fg each for other player to get a quick socket quest

So first of all premap for me its like making the game with my level 1... joining with my rusher and teleporting to all the quest in advance so i know the route when people are in game

is there any place that i cant premap, that would cause problem.
Like arcane i thing would be one,,, jeryn will be block
any other like that?

It will end up costing you too much time.
A character with good faster cast rate with enough mana will do it easily.
Most of your time is within Act 2 anyway.
Act 1 is simple with just going from Floor 2 to 4, which is very small when compared to the size of the map in hell mode.
Act 3 is just going from Floor 2 to Floor 3 after doing the council.
Act 4 = Chaos run

Better off with act 3 ready with the 3 organs so when everyone gets to act 3 you just do trav but you will need a fresh char to make the game then swap char after every one in games

Its fine as long as you dont kill anything
If youre worried about jerhyn being blocked
Do lost city first before far oasis