A group of Micronauts cameo in the background of New Mutants #50 - Rann, Mari, Acroyear and Bug, plus possibly Fireflyte. Full size, on an unknown mission I guess. Also visible, though not relevant for the Project, are Nexus and Grimjack from First Comics (Grimjack being the mercenary the Starjammers meet with, albeit using the alias Haggard).
For the Micronauts, based mostly on publication dates, this would presumably take place during the long hiatus between their second series ending and them officially reappearing; for Bug, Rann and Mari, this would be between Micro2 20 and BUG; for Acroyear, simply after Micro2 20, and for Fireflyte, hard to say, as I'm not sure if this would count as Fireflyte III.
Micronauts in New Mutants #50
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