Theres quite a few tools out there.
Paddle likes to reject people - LemonSqueezy is an up and comer

But... MoRs will charge all the taxes from day 1

You (in 95% of cases) wont be liable for taxes in a region unless you hit a certain threshold of sales in that region (Some places $1k, others $10k+) - it could take a while before you MUST pay taxes in Random Country.

Using an MoR is great if you really dont want to care about it

But you're actually losing a lot more than the their "Fees".
You users will end up paying 20-25% more for your service because the MoR charges taxes from day 1.

Stripe has some tooling to track your tax obligations in regions, and partner tools to do the filing.

IMO (What I plan to do) - Stick with Stripe till you cross thresholds for big regions (EU, US etc) and then look for a solution.

Really depends on your tax jurisdiction and likely the type of customers (consumers or businesses with VAT ID) and pricing structure (whether it makes to complicate your checkout process verifying whether customer is tax exempt)