Helpful shortcuts and menus that are easy to miss

Before queueing up, you can press X/Square on a Night Lord to queue up for multiple Night Lords at once. This vastly cuts down on queue times once you got past the Sif on crack suffering from multiple personality disorder. Similarly, you can also press Back/Select to choose between All Options, Undefeated Night Lords or Copy your last expedition settings.

Wonder what Endure does? Press Start to access your inventory, then while having a weapon selected, press R3 for a description of what a Weapon Art does

Wondering which one of the two Greataxes you picked up has more Attack Rating? Press Start to access your inventory, press RB/R1 to switch to the Status tab. Under your Base Stats you can see all your Weapons (called Armaments) and their AR in a neat little list. This helps especially if you can't be arsed memorizing every weapon's scaling from the Codex.

In the same screen (Inventory -> RB/R1 to Stat screen), you can see all your buffs and their names on the right. If you only see Icons, press Y/Triangle to swap to the name display. Press R3 to get a brief description what every Status does. Instead of only seeing "Improved Incantations", you can even see the Percentage amount in this screen.

While looking at an item, hold Y/Triangle and press L3 to ping an item

While looking at an item, hold Y/Triangle and press Left or Right on your Directional Pad to switch through the items you're facing. No more running around like a headless chicken trying to look at every item on the ground.

Inventory space is limited in Nightreign, but did you know that you can instantly use an item that's lying on the ground by holding Y/Triangle and pressing D-Pad up? Yeah, all those items you usually leave on the ground unused can be used as a quick temporary buffs without having the hassle of inventory management. Make use of that Exalted Flesh you'd normally just leave on the ground!

You can press X/Square to instantly discard one of the items on your reward screen. Very helpful so you don't have to first pick the item up and potentially drop something else you want to keep.
Similarly, you can discard items by pressing X/Square in your Inventory. Maybe that Bow you don't need anymore has a great passive on it somebody else might want.

Press Start to enter the menu and Y/Triangle to access your emotes.