Scale walking movement without affecting world scale

I have a HTC Vive room setup with a bit more than 5 by 5 meters. The virtual world is a bit bigger than that, but no big enough to require any teleportation movement. Currently when you move 1 meter in the real world the Vive Trackers tells Unreal to move in the virtual world by 1 meter as well.

To be able to move in a larger part of my virtual room my idea was to scale the plane translation motion of the user in the with a factor (maybe 25% increase). So when the user walks 1 meter in the real world they are moved 1.25 meters in the virtual world. I know that you can change the world scale, but that is not what I want since that would make the user 25% taller as well.

So do anyone got any ideas how to solve this type change of movement behavior in Unreal?