Hi @DanSrokosz ,
Really great question and I can fully understand any potential hesitancy. It will depend on the theme, the language, how much things are customized such as apps etc.
I did a test change on my test store to give you an idea:
It looks like the buttons and some other aspects have changed, but the product descriptions/titles/homepage text seem to still be in English so you’d need to change those manually in the Language editor.
There are some apps you can look into helping with this too but you may not need them. The one I like the most is Langify. There’s also the Shopify help guide for this here.
