I usually found it easier, to combine the Enhanced Input X and Y value into a Vector with the Make Vector node (Z axis stays disconnected - gets zero), and feed that into on e singlee “Add Movement Input” World Direction, and let the Scale Value untouched with 1.
Like this:
Afaik, that Scale Value works only in the 0-1 range, since the “Add Input Movement” is using the Character Movement Component and so the scale goes always from Zero to whatever Max Speed your current movement mode has. So to get more speed, you have to raise the max speed in the Character Movement component for this movement mode.
And of course, for less sluggish movements, play with the accelleration and decelleration values in the Character Movement Component.
For 2D you might want switch the Y and Z axis in your IMC, if you are playing it in a vertical plane and not on a horizontal plane, thats lying flat on the ground. Or just use the “Make Vector” Node to connect the Enhanced Inputs Y output to the Z axis instead of switching it in the iMC. Whatever is more consistent with Controllers and Keyboard behaviour ^.^
I guess, a First/Third Person Character is viewed from a different angle or side, than a Side Scroller or Top Down Character, so some axis might not move in the correct direction for all modes.