horde: get on the quest find thrall, use voljin hearthstone and get to the senjin flightpath. take it to org. once on flightpath logout. wait 10 secs. log back in. once loaded logout before 3 seconds (basically when you see it load the zone chat for the area you are in. i recommend a /camp macro. to get a level 10 in there you must summon via summon tickets or raf. do the same thing. even in org you have to relog every 3-4 secs or it will teleport you. good luck
alliance. get to the quest where you go to darn. do not go to darn take teleporter. the boat is on a 3m 50s loop timer. if the boat is not there when you teleport immediately alt+f4. if not after 2 secs you will be ported to darn. you have to be on the quest or once you take the boat you will be hit with a this is not your time and sent back to mop.
other things you can do. logout on boats to teleport to the area they are supposed to go or it sends you out in the middle of nowhere. you cannot take any portals or anything to any other map id's however if you are on the quests find thrall or any in that area chain you can go into other maps via boats and zepplins. again use logout method.
when in other map id's you can only visit one area of the map at a time. if you go to another area there will not be any mobs. to fix this just logout and log back in. do not try to go to legion areas, outlands, i have not gotten into draenor yet via any method. you can get into dragonflight and do things there.
HUGE HEADS UP. if you are alliance you cannot go to the far north west of any map or it will think you are out of the area and send you to the xyz coords where it would normally teleport you. it will loop every 4-5 secs. you cannot hearth etc. to fix this just partysynch with someone and it will teleport you to mop area.
same applies for horde. you cannot go to near the same area your thrall quest is on any map or it will do that as well. for the thrall coords.
you can get into dk and paladin class halls but no matter your class the pal place will stunlock you. you can get out but it is annoying as shit they cant teleport you so just a warning as to how annoying this can be.
you can enable timewalking but you cannot queue for anything. all vendors work and even the ah "seems" to work. the only way to access it is to know which server it connects you to when you login and do the old "instance aborted trick"
from way back when. using this you can prevent yourself from being auto phased into the timewalking server. depending on the area you may or may not see other players, you are still a timewalker tho and if done correctly in a certain quest that phases you, you can trade to people who are not time walkers. i have sold a 6 stack of gems for gold cap so if you figure it out enjoy the free money i just gave you.