Yes — buying a username as a gift works the same way as buying one for yourself, with one extra step: being clear upfront about who the account is actually being handed over to.
It helps — flagging that the handoff should go to someone else avoids any confusion about who's actually receiving the account.
Open the vault, pick a listed username, and DM the contact handle shown on the site to arrange payment — there's no cart/checkout, it's a direct conversation with the seller.
Crypto-only. See the Terms of Service for the full payment and delivery policy, including the sale-finality and 72-hour issue window.