Activision Blizzard confirmed several release plans for 2020 during its fourth quarter and 2019 financial results conference call.

Here is a summary, via Niko Partners senior analyst Daniel Ahmad on Twitter:

Activision

A new Call of Duty title will be released in Q4 2020.

Several “remastered” and “reimagined” titles are in development, which will be announced later in 2020.

Blizzard Entertainment

Diablo Immortal will enter alpha testing in mid-2020.

World of Warcraft Classic will receive new content just like other Blizzard Entertainment titles.

King

King will invest in new titles for 2020.

It is worth noting that in February 2019, the Pan European Game Information rated a still unannounced Call of Duty: Modern Warfare 2 Remastered. This could be one of the remastered titles Activision is referencing.