FBXImportForcedFileAxis [y|z];
Use this command to "force" the FBX plug-in to consider the data in the file as if it is natively generated with the user-specified axis. There is no UI equivalent to the FBXImportForcedFileAxis command, and it can produce unexpected results as the command changes only the incoming file axis in the global settings.
For example, a plane created in 3ds Max's Z-up world would have the following vertex coordinates: (0,0,0) - (1,0,0) - (1,0,1) - (0,0,1). (This plane would look like a sheet of paper on a table, with the table being the XY plane at Z = 0 elevation.) On import into Maya, using the FBXImportUpAxis option, the plane would rotate so that the it would appear to be in the same position in Maya as it is in 3ds Max. Therefore, in Maya, the plane is on the XZ plane with the Y = 0 elevation. (Provided Maya is set to the default Y-Up axis.)
If you use FBXImportForcedFileAxis to force the axis to Y-up on import, the Maya plug-in will NOT apply any conversion to the axis. This is because, with this command, the plug-in treats the File and the System axis both as Y-Up, making the plane becomes perpendicular to the table, on the XY plane with Z = 0 depth.