The max rise, I think is 7.5 or 8 inches. So you will need steps. You could do two steps the entire length of the space. But make them deeper than the ones you had there before, for a more relaxed movement between the spaces. Or you could do a glass type railing to keep the open look you now have:

See the steps in this space: and

How about a low wall?

Agree with above.

Agreed to leave out the railings. This will be a great open concept space.

I would keep it open and make steps the full width of the room.

I would disagree with most. The handrail is about 'function'. I think a lot of people would feel more comfortable knowing there was something to hold onto just in case. It's like being in the shower without anything to hold onto. I would say that a very simple rail would be best.

I agree with 2 step the length of the room.

I have 0.9m depth  sunken  living room.

Six risers  and provision of  guard rail for safety.

I would do 2 steps the length of the room