They're useless on this matter. They dance around the issue and ultimately advise you to pay for an 'expert' to customise your store when really it's a basic functionality required for all international sellers. It's simple
Europeans don't like to be surprised with added taxes
Americans & Canadians are used to it
So if you're selling in Europe you want to have taxes included, but when you sell to i.e Americans you don't want to charge them the extra 20%.
This is a glaringly obvious oversight on Shopify's behalf and there are countless threads on the matter all of which result in Shopify staff fobbing us off with explanations that skirt around the issue and offer no solutions other than to hire an 'expert' even if you're already being fleeced $2k a month for 'plus' services which are an absolute joke as it is. My advice is to move to a better platform, there are plenty of options now that actually care about the needs of businesses