Hiya, just dropping a folder which has all of Brawlhalla's stage backgrounds without colour and blurred. It's a must for visual clarity. Images look like they have film grain but as the example shows its imperceptible.
https://mega.nz/folder/iYRkxKID#y03alxL6Vr1_BxcENHjTCA



To install copy the images from the linked folder and paste them into:
C:\Program Files (x86)\Steam\steamapps\common\Brawlhalla\mapArt\Backgrounds



Hit replace all, close the folder and your all sorted :)