Thanks for this info, Johnny. There is not much news about this model.
Apparently, the keyboard layout is exactly as this seen in TT3000. But key caps are different - they are more like those known from IBM PC/XT

The article says that the added value of TC2356 would be some "professional software". I know that one of these programs is
TimeWord+, which was also offered for TC2068 as a cartridge. Do you think this program is available anywhere?
EDIT: OK, I have found the DCK file.