Answer
Users, who should have moderation rights before the meeting, for example to be able to start a meeting themselves, must have a Zoom account with their TU Wien email address. When creating meetings via TUWEL, enter the TU Wien e-mail addresses of the users in the "Alternative hosts" field. Before alternative hosts enter the meeting room, they have to log in with their Zoom account.
Furthermore, it is possible to give users moderation rights during a meeting. This can be done by right-clicking on the users in the list of participants and assigning the role "co-host" to them. However, co-hosts cannot start meetings themselves. During a meeting, also the role "host" can be transferred to another person in the same way.