Learn Dutch: Ik heb nog een retro opdruk te ontwerpen. - I still have a retro imprint to design.

Even though opdruk is a de-word (which normally means its adjective gets an -e after een), retro is an invariable adjective. Many modern loanwords and adjectives ending in a short vowel (like gratis, plastic, or roze) never take the -e suffix.

How is Ik heb... te ontwerpen different from Ik moet... ontwerpen?

While both express that something needs to be done, moeten expresses a direct obligation ("I must design"). The hebben te + infinitive structure translates directly to the English "to have something to do." It focuses more on the existence of a pending task or object (een retro opdruk) that is sitting there waiting for you to complete it.

Could I change the word order to Ik heb nog te ontwerpen een retro opdruk?

No, that would be grammatically incorrect in Dutch. Because te ontwerpen acts as the non-finite verbal part of the clause, it must be pushed to the very end of the sentence. The direct object (een retro opdruk) has to come before it.

What kind of "imprint" does opdruk usually refer to?

Opdruk literally translates to "on-print." It is the standard word used for a graphic, logo, or text printed onto a physical object, most commonly clothing like a t-shirt or a hoodie, or promotional items like mugs.