Character Movement Component - Changing directions is not fast enough

I’m working on an isometric style game where movement is done with WASD, allowing for 8 directions of movement. When the character moves, I update the 2D flipbook used to draw the character based on their X and Y velocity.

Unfortunately, I can’t seem to tweak this quite right. When the player changes from moving UP to moving UP/RIGHT, I can see the X velocity of the character will transition from the max (somewhere around 250) to 0 over maybe half a second. For this half of a second, the UP flipbook is still in use even though the character is now moving UP/RIGHT.

How can I set this movement up so that there is no acceleration? I need to have it so pressing up will immediately set the velocity to the maximum in that direction and when that button is released, it instantly stops. I’ve tried setting acceleration to a crazy amount (I think 100,000) and breaking and ground friction all the way up but it doesn’t seem to have any effect.