Hiroyuki Sanada has been cast in an undisclosed role for one of the two Marvel Studios' Avengers sequel, according to Deadline. The Hollywood trade said Sanada is expected to film "a supporting role on the upcoming Marvel film Avengers: Infinity" - no "War" at the end of that, but presuming an editorial oversight over there it would infer Avengers: Infinity War.
The casting for three of the four members of Thanos' Black Order have yet to be confirmed, so it's possible Sanada could be playing Corvus Glaive, Proxima Midnight, or Cull Obsidian. Tom Vaughan-Lawlor said earlier this year he is playing Ebony Maw.
Joe and Anthony Russo have said they've completed most of the Avengers: Infinity War filming and have segued to the fourth Avengers film, but said they will jump back and forth and do some additional shooting on Avengers: Infinity War.
Sanada is currently co-starring in TNT's The Last Ship, and played Shingen Yashida in 2013's The Wolverine.
Avengers: Infinity War is scheduled for release May 4, 2019, with the fourth Avengers film on May 3, 2019.