This is a vector (EPS) template of the background plate for a Legendary item inspired by the graphics used in Fortnite: Battle Royale. I created this vector from scratch, and in the zip file you'll also find an extremely high resolution JPG version (10240 x 5760) in case you don't have vector editing tools.
Furthermore, I created an animated version in 4K that you can use in your videos and gifs. It is loopable and lasts a duration of 5 seconds:
You can easily shift the hue/saturation/lightness of these items to cover Uncommon, Rare or Epic items. If you drop the saturation down to 0 you've got Common.
It should be noted that the downloadable versions of these items do not contain watermarks and I'm making them available under Creative Commons Attribution 4.0.