Yes, you can. Exam Reader Cloud only supports one key for an exam  but in the mobile app you can save/load unlimited number of keys locally.

Download the exam as DOCX or JPEG and paste/edit the sheets so that you can mark them with your choice of versions (groups) before printing. The first version (group) key will be the one you entered on the cloud app.

Enter as many keys as you want on the mobile and save them with different names (i.e. Exam 1 Group B, Exam 1 Group C...etc).

After collecting the answered sheets from the students, group them with the marks you edited and grade the first versions (A), then send the results to cloud. Then select the same exam but before grading the B versions, load the local B key and grade them, send the results to cloud. Repeat this step for further versions.