They can keep Egi lore as it is but function as a lesser version of Demi if lore is really that important. Temporary summons you use during Demi summon downtime, no requirements to summon them like Bahamut or Phoenix. They share the same mechanics and buttons.

I really hope they blend both pets into a single interface because it personally bothers me how we need two separate buttons for Egi and Demi commands.
Still, they need to fix the annoying pet ghosting and very short distance limit between the caster and summon for temporary summons to move forward.