Warsaw's workcation list asks for an "employment contract or employment certificate in their country or professional portfolio showcasing digital nomad, remote worker, foreign talent or freelancer status", so for Preply teaching you'd go the portfolio route.
What makes it convincing is showing you're actively earning from students abroad now:
- Your Preply tutor profile (public link or screenshots) showing your rating, hours taught and how long you've been active
- Preply earnings or payout history for recent months
- The matching payouts arriving on your bank statement in your name
- A short cover letter explaining that you teach English online to students outside Thailand, with no Thai employer
- Your Polish business or tax registration, if you invoice as a sole trader
Also from Warsaw's list: a Polish ID card (both sides) as proof of residence, a bank statement with a closing balance of at least 500,000 THB (or the equivalent) for the last month, showing your name, the balance and the date, and a Polish criminal record certificate. Bank statements need to be in English or come with a sworn English translation.
Warsaw embassy DTV page:
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