After reading some topic on the forum can you tell me if I’m right.
CP “Axis Mapping” can replace CP “Axis Location” on Exports, but not for Master.
So an alternative to use “Axis Location” on Masters and Exports is to use CP “Axis Mapping” + CP “Axis Location” for masters ?
Masters define with their Axes Coordinates the internal design space, which by default is also the external design space that font users see. You can redefine the external design space by either adding Axis Location custom parameters to instances or by adding an Axis Mappings custom parameter to the entire font (which overrides Axis Location parameters, if set).
See also the recently updated tutorial (section Axis mappings and locations):
Oh, I didn’t notice that tutorial was updated thanks @FlorianPircher .
So I have my answer :
For each master in Font Info > Masters, add Axis Location parameters with appropriate external coordinates. You can skip the step if your external coordinates are the same as the internal coordinates.
We just discovered some problems with the Axis Mapping parameter. So using just Axis Location parameters in the masters and instances (as needed) is easier to set up and works.