I have contacted Samsung by email and phone to be told that it is at present not possible to have auto correction (predictatext), hyphenation or capitalization on the physical keyboard cover.
It is available on the on screen keyboard though.
I was told to put this issue on this forum, to request if possible that Samsung put this into any software updates in the future.
I am very pleased with the Tab S6 and have had no issues with the cover coming unstuck like some people.
With the pen also being an issue with some, I find that if you lay the pen in the recess flap, nib to the right, charging point facing out it falls into place perfectly.
I do hope that Samsung can look into my keyboard issue at some time in the near future.
