For those that don't know.
Xenagos, God of Revels - 3RG
Legendary Enchantment Creature - God (Mythic Rare)
As long as your devotion to red and green is less than seven, Xenagos isn't a creature.
At the beginning of combat on your turn, another target creature you control gains haste and gets +X/+X until end of turn, where X is that creature's power.
Yes. The legend rule only applies to legendary permanents with the same English name, and the planeswalker uniqueness rule only applies to planeswalkers with the same subtype. Xenagos, The Reveler is a planeswalker, and Xenagos, God of Revels is a legendary permanent. They have different names. Nothing about this situation prevents you from having both on the field at once.