The black strap has been changed to white, and the previously red ribbon on the belt plate is now green. The inside of the strap has also been changed from red to green.
— All Elite Wrestling (@AEW) July 15, 2021
You can see the old belt below for comparison.
Perhaps the belt has something to do with the flag of Rusev’s birth country of Bulgaria, which is white, green and red, but there doesn’t appear to be any red anywhere on the new belt.
On Monday’s AEW Dark Elevation, Miro cut a backstage/video promo and said, “This title, it has made me different. So I will change it like it changed me.”
You can see the promo at around the 1:17:45 mark in the video below.