YES, it can👍
The MFC-J6940DW is what is known as an A3 full-duplex device.
That is:
A3 duplex copier
A3 duplex printer
A3 duplex scanner
A3 duplex fax

For more complex A3 scans (CAD, construction or circuit plans, maps, etc.), I would recommend scanning from the scanner glass, despite duplex capability.

happy duplexing 😆😍

Kann es......; Lesetipp:
https://www.brother.ch/de-ch...

It can, duplex scan A3 in one pass.