I now got two new sources claiming that Panasonic will announce a G90 by end of the year. The second source shared some more details:
Pana might release the new G90/95 as an answer on the BlackMagic pocket.
The new G90 will have the sensor of the GH5s, have a good IBIS and a price around 1200-1300
From trusted sources we know Panasonic will announced the new LX100II on August 23. Would be nice if Panasonic would still give us this new “mini-GH5s” version at Photokina too!