we've been running multi-lingual ads for thebirthposter.com for a very long time and had no issues with it, but YES - every step of the funnel is the native language.
but you can find success with an ENG-only approach, just that's not really scalable unless you have a great offer and a proper stack of shock-value content for ads :)
Shopify's higher tier sub allows you to easily translate the whole site :)