There is currently very little information regarding Black Ops 4. More will be announced on May 17th during the community reveal event.
What they did with the last remastered I don't have high hopes.
2/3 of the weapons will.be released during events.
They will cut out some maps and make a nuke town ww2 setting map.
Because everybody loves nuke town.
And I also see.them not including co-op campaign.
Buddy and me have played the campaign co-op each difficulty at least once.
There are two things in my mind that would make WaW possible...
1) 10 year anniversary on a Treyarch release year.