From Teletraan I: The Transformers Wiki

The Alpha Quadrant is a location in the Beast Wars portion of the Generation 1 continuity family.

The Alpha Quadrant is "someplace far, someplace barren." The Axalon was ordered by the High Council to undertake a secret mission: drop Protoform X on some featureless rock in the Alpha Quadrant and never speak of this again.

But then the Beast Wars happened instead. Dawn of Future's Past

(Note: The Alpha Quadrant is named only in the BotCon 2006 story, Dawn of Future's Past.)