I want to change my suffix label on decimal grid/measured grid coordinates for a map canvas in the print composer from "N" or "E" to "m.N" and "m.E". How can I achieve this?
While some more input on your side would have been helpful, here is the solution:
draw coordinates in your map canvas' properties and change it to
custom/user defined. Click the greek "E" next to it and enter
@grid_number ||if(@grid_axis='x',' m.E.',' m.N.')