Well, this came out of nowhere. In an article by Deadline detailing the media history of similarly named heroes like Deadpool, Deathstroke, and Deadshot, the Hollywood trade claimed that Marvel character Deathlok was being eyed for an upcoming MCU film.
A version of the character has appeared on the ABC series Marvel’s Agents of S.H.I.E.L.D. (portrayed by J. August Richards) and there’s been rumors that Marvel Studios may use the character soon.
Because of how casual the whole thing was shared by Deadline, it’s hard to determine if there’s anything concrete behind it. But if the film division does have plans to bring Deathlok into the fold, three things could happen: 1) they could finally acknowledge Agents of S.H.I.E.L.D. canon by bringing J. August Richards in, 2) they unintentionally allude to AoS canon the same way Captain Marvel gave Carol Kree blood to survive, or 3) they ignore what the show did completely and introduce him their own way.
Of course, it also depends on what film they put him in. Films like the Doctor Strange sequel and The Eternals can be ruled out, leaving Black Widow or Shang-Chi as the most plausible options. Black Widow is reportedly set in the past so while they likely won’t use present-day Deathlok from Agents of S.H.I.E.L.D. in this instance, a connection may be made. Maybe they can have Shang-Chi fight him in his film.