I have solution to redure LCP/CLS. If you need it, contact me Telegram @tungnlt 

Have you got BfS? I have solution for this. If you need it please contact me Telegram @tungnlt

I see you finnaly got the badge "Build for Shopify" for your app. How did you improve the LCP?

Goto your app listing management, scroll to "App category" section, and send an appeal: