Is MCU teasing a Mr Sinister appearance?

The Marvel movies have been teasing Mr Sinister quite a bit. At the end of X-men Apocalypse we see the vial labeled “Weapon x” being placed into a briefcase with the name “Essex Corp” stamped on it. In Deadpool 2 the name of the orphanage where Russel lived was The Essex House for Mutant Rehabilitation. …