Hi 93562867!
Our forum is focused on English, so we will answer your question in English. Thanks for your understanding!
Back to this case, can we understand you want to hide two external users’ identity to each other in Teams meeting? In other words, you want to internal users cannot see external users’ email address in participant list, right?
If so, you cannot hide their address if you invite external users to the meeting. But you can try to change the meeting to live event and it does mask who is in the meeting. For more details about how to schedule the live event, please refer to:
https://support.microsoft.com/en-us/office/schedule-a-teams-live-event-7a9ce97c-e1cd-470f-acaf-e6dfc179a0e2?ui=en-us&rs=en-us&ad=us