The way we are trained to do it is:-
On all Chinese Approach charts there is a QNH Feet to Metres correction table.
For example ZBAA ILS 01 chart 11-1
So when Mr ATC say "descent to 1500m" you check the table and set 4,930' ( or as close as you can, in this case 4,900' ) on your FCU/MCP.
You cannot simply set 1500m directly on it.
I don't know why you can't just can't turn the knob until you see 1500m on the PFD.....maybe it's just our silly Flight Ops people?