Is it possible to create different QR codes for the same content?

Yes. Even if all the input data and the selected error correction level (ECC) are the same, there are various graphic representations of clear and effective QR codes with the same content. The reason is that there are eight possible data masks that affect the mode. The existence of these masks is to prevent some module modes that are difficult to decode.
Not every data mask is really suitable for every content. However, many QR code generators do not take the test and determination of the best mask seriously, although this may cause the QR code to be unclear (but still effective).