A:AnswerThe Brother MFCJ5855DW does support envelope printing. The machine can load up to 10 envelopes from the standard paper tray and up to 20 from the manual feed slot. The machine can support cardstock paper of up to 58 lbs. Cardstock paper above 58 lbs is not supported by the machine.
A:AnswerThe cartridges seem to be designed to fit in it. not saying something else might not work but you would need to copy the Cartridge design first
A:AnswerUp to 19200 × 19200 dpi (interpolated) *
Up to 1200 × 2400 dpi (optical) (from Scanner Glass)
Up to 600 × 600 dpi (optical) (from ADF)
*Maximum 1200 × 1200 dpi scanning with the WIA driver in Windows 7 SP1, Windows 8.1 and Windows 10 (resolutions up to 19200 × 19200 dpi can be selected using the scanner utility).