UPDATE: Relic have indeed announced that the game will be the third entry in the Company of Heroes series is now on the way, with some details of the new game being revealed in the livestream below.
The studio behind the Company of Heroes series, Relic Entertainment, has a countdown up on their Twitch channel right now that seems to suggest a new game with a World War 2 theme is about to be announced in the next few hours.
The Company of Heroes franchise has, to date, always focused on the WW2 era, so it seems to have risen expectations in the accompanying Twitch chat. The Stream's countdown timer is an ariel photo of Italy and has occasional black-and-white film footage of the region, which would suggest that the game, Company of Heroes 3 or not, would be set in the Mediterranean.
Company of Heroes 2 has been getting some basic small updates but hasn't had any major new content for some time now, so it makes sense that Relic may have been working on the sequel for a little while now.
It's been eight years since Company of Heroes 2 was released so it's probably about time, too. We'll be sure to keep an eye on the announcement and report any further details as we learn it.