"3.6. Please note that if you offer digital content to third parties for a fee through PRINTABLES STORE, the income from such activity will most likely be considered business income and the operation of a business. In this regard, you are fully responsible for ensuring that such activity complies with the applicable laws and regulations that apply to you and such activity, including any applicable tax regulations and obligations, including any applicable VAT. You acknowledge that when setting the price for digital content in the Store, you are required to state the Selling Price so that it is inclusive of all taxes and fees that are associated with the sale of digital content under applicable law ("Selling Price"). You, as the Creator, are responsible in particular for ensuring that the Selling Price is the final display price to the Buyer."
and
"4.5. All tax obligations, levies and reporting related to the Creator's revenue from the sale of digital content are the sole responsibility of the Creator. In this context, the Creator may use third-party services such as STRIPE TAX or specialist accounting firms. PRUSA is not obliged or authorised to provide the Creator with any accounting, tax or legal advice in this context."
So if that means that creators need to manage the remittance of sales and VAT, that'd be a pretty big deal for me. I'd not expect to make more than a couple hundred bucks a year from clubs, which would not be worth the hassle of figuring out how to pay sales taxes and VAT for memberships paid by EU members.
I checked Patreon, and it seems they do collect taxes and VAT (for many US states and countries at least), and I believe they take care or remitting the sales taxes and VAT where they collect it at least. That way (from my understanding), the creators only need to worry about their own personal (or business) income taxes, and not paying the local taxes for every transaction. This seems like a reasonable approach.
I looked at STRIPE TAX, and it looks like an administrative burden for the average person without a business (with a business it would probably be worthwhile though). So if I understand this correctly, I cannot see any way that using a Printables club would be worth my time, considering the associated hassle in trying to pay every tax related to the transactions.