Can I buy Pro without revealing who I am?

Yes, with two standard tools. For the receipt, use an email alias: Apple Hide My Email, DuckDuckGo Email Protection, SimpleLogin, Firefox Relay, or addy.io all forward to your real inbox without exposing it. For the payment, use a masked card: privacy.com in the US generates virtual cards that work with any name you type, and many banks and services elsewhere (Revolut, for example) offer disposable virtual cards that do the same job.

At checkout, Paddle asks for an email, a payment method, and a country (plus a postal code in some regions) to calculate tax. The alias receives the receipt, the masked card carries whatever name you gave it, and the tax location narrows you to a region, nothing more. Keep the alias alive though: the receipt email is your proof of purchase and your channel for a refund.

Combined with a phrase account, no single party ends up holding the full picture: your bank sees a card top-up, Paddle sees an alias and a masked card, and we see only that a public key became Pro.