I have a very similar issue and bookkeeping is a nightmare. I don't need Stripe to calculate sales tax, I only need it to import the information from Squarespace so that I can easily import everything to Quickbooks.
For example, if I make a $6.00 sale, Squarespace collects an extra 0.42 cents for sales tax. Stripe processes the $6.42 transaction and deducts a 0.31 cent fee, giving me a payout of $6.11. When Quickbooks sees that payout hit my bank, I have no way to separate out what was sales, what was tax, and what was a fee.
It's so frustrating because our in-person POS with Square does everything 100% automatically!
Any advice?