How to Leave mission in Nioh 2

To quit your current mission and return to the starting point on the world map in Nioh 2, you need to use an item. In your inventory you’ll find the Divine Branch Fragment; use it and you’ll be returned to the world map, although you’ll lose all of your current Amrita in the process. It’s therefore a good idea to grind out some more Armrita if you’re close to the amount needed to level up, and then do so. You’ll find that you can use the Divine Branch Fragment as many times as you like.

1-Himorogi Fragment

The Himorogi Fragment is obtained at the start of the game and is an item which is not consumed on use. However, choose to use it and you’ll forfeit all of your Amrita to quit the mission.

”A splinter of a sacred tree used as a holy vessel in religious rituals. Uses up all of your Amrita, but allows you to quit a mission and return to the starting point.”

Remember, this item is infinite use, so there’s always a way to quit a mission if you’re really struggling.

2-Himorogi Branch

Your other option is getting hold of a Himorogi Branch which allows you to quit a mission and return to your starting point without losing any Amrita. This is a rare item that can be found as loot in missions, or earned from mission rewards. Unfortunately it can’t be purchased from vendors.

There is no downside to using the Himorogi Branch to quit a mission, apart from the fact it’ll be used up when consumed.

source:(1)(2)