Litchi does not directly support exporting to Google Earth Pro.
What you are describing is Virtual Litchi Mission which is a separate product. While many people who use Litchi may also use Virtual Litchi Mission, there is a separate forum specifically for Virtual Litchi Mission:
I mention that in the event you do not receive the answer to your question here.
When you export, are you selecting the “Export as CSV” option or the newer, dedicated export icon at the top of the VLM window?
In the Virtual Litchi Mission new version V2.7.3, I used the dedicated button. But it’s not working anymore! Just like the dogrid creation button or the orbit creation button!
I’ve reinstalled everything, including the previous version (which doesn’t have the dedicated buttons for creating orbit and grid) and even this old version doesn’t connect to google earth !
The current version of VLM and the older version of VLM (2.5.0) use a completely different method to export the mission to Google Earth. The old version (2.5.0) has you specify a “Watch Folder” and you choose “Export to CSV” to send the mission to Google Earth Pro.
The latest versions of VLM (2.7.3) have a dedicated button at the top to export the mission to Google Earth where the complete mission data is sent and not just what is in a CSV file.
If neither the old or new versions of VLM are sending data to Google Earth, perhaps the problem is not with VLM but with Google Earth. You could try re-installing Google Earth Pro.
The original “Virtual Litchi Mission” is an application that only runs on Windows. However, someone else reverse-engineered VLM and make an Extension for the Chrome browser. Perhaps this will work for you.