Yes, this is possible. onSET German and onSET English can be taken simultaneously in the same examination room.

No. You may offer onSET exams according to you schedule any time – except during maintenance work. 

Yes. Test takers must be placed at sufficient distance or have a screen between workstations. It is extremely unlikely that two people will receive the same texts in the same order – however, individual gaps and answers could be spotted by glancing at a neighbour’s screen.