Artifact Signing: can a Spanish sole trader use an unregistered trading name in CN and O?

I am a registered self-employed developer (autonomo / sole trader) in Spain, not an incorporated company. I develop software under the name Donatello, which is not a registered trading name or company. My official documents identify me by my personal legal name; I have no official document bearing the Donatello name. I have created an Artifact Signing Basic account but have not submitted identity validation or signed binaries. The quickstart mentions Organization/DBA validation, while the FAQ says CN/O cannot be customized. I understand the portal preview is not approval. Could the identity-validation team confirm whether a Spanish sole trader can obtain Public Trust signing with only Donatello in CN and O, providing the true personal identity privately? If not, would an OEPM-registered Spanish trade name owned by the sole trader be sufficient, and what exact documents would be required? Would the resulting CN/O show the trade name alone or also the personal legal name? Please also clarify any applicable business-history and billing-account-type requirements. I want to establish the compliant route before submitting documents or paying to register a name, not bypass identity verification.