Whether they’ll appear in the film or not, I can’t say, but as for Godzilla: Kaiju Planet’s history… Rodan confirmed! And Anguirus, Dogora, Dagahra, Orga, and Kamakiras! [x]
I can’t translate all of this, but it seems the timeline is more or less like this. Someone more fluent–or more willing to spend time looking up kanji– can help.
May 1999 - Kamakiras attacks Boston/NYC area. 2.5 million deaths
September 2002 - Dogora in London. 3.9 million deaths
November 2005 - Rodan and Anguirus. Maybe something about Hedorah. 8.2 million deaths
December 2017 - Dagahra in Australia. 6.7 million deaths.
May 2022 - Orga in Turkey. 11.5 million deaths.
2030 - Godzilla appears.