You can download it here: panasonic.jp/support/global/cs/soft/download/d_lumixtether_b.html
Press text:
Panasonic announced the release of “LUMIX Tether for Streaming (Beta)” on June 8, 2020. The beta software program for Windows is derived from conventional “LUMIX Tether (Ver.1.7)” with an additional display option for the cases where this software is used for live streaming purposes. It may help user convenience in the growing self-streaming opportunities.
As “LUMIX Tether” is a software program originally designed for tethered shooting, GUIs such as a focus area mark as well as control panels are displayed with live view images on the PC monitor during USB tethering. However, these graphic items become a hindrance when the software is used to capture camera view for live streaming. In response to the demands of customers to resolve this issue, LIVE VIEW mode has been added on “LUMIX Tether for Streaming (Beta)”. It enables displaying camera view only, making it easy for the separate streaming software to read it. Users can choose to show or hide these graphic items during USB tethering according to the usage purpose.
“LUMIX Tether for Streaming (Beta)” is provided as a pre-release version that is currently still under development. Please note that this software is not eligible for operation warranty and customer support.
Compatible models: DC-GH5, DC-G9, DC-GH5S, DC-S1, DC-S1R, DC-S1H
Richard Wong shows you how this works: