Change Banner Images on 3 Shops: Shopify, Etsy, & Bonanza

Want to piece together a new "background" for me for my pages on Etsy, Bonanza, and Shopify. Files are already "ready" along with mock ups in a directory I will share with you. No need to search and look for/find images or do crazy design. I just need 3 files, one for each of the 3 sites, to fit within the measurement standards for each sites' store banner without it looking stretched or distorted. Basically, it's a really sparkling Refractor card background with somewhere placed on it the logo, the blurb, and the ballpark image on it....it's just about placement....so it looks sharp, and with a refractor background behind the logo....it might look too busy? Maybe the refractor image becomes just a thin border around it all....which is still attractive and attention grabbing