Ashaya& #39;s last ability and Blood Moon both apply in layer 4. Ashaya changes what Blood Moon applies to, and not the reverse, so Blood Moon depends on Ashaya. That means Ashaya is always applied first. Your nontoken creatures become Forest lands in addition to their other types.
Ashaya is now a Legendary Creature Land — Elemental Forest. Now we apply Blood Moon. Becoming a Mountain takes away Ashaya& #39;s land types and abilities but leaves everything else. Ashaya is now a Legendary Creature Land — Elemental Mountain.