In addition to the 20-70mm f/4, today Sony also announced the development of a new FE 300mm f/2.8 G Master OSS lens that will be released in 2024. Sony currently has the 600mm f/4 and the 400mm f/2.8 G Master lenses.
The full press release of the announcement can be found here:
G-Master™ large-aperture telephoto lens with focal length of 300mm F2.8 is under development