You installed the latest Crosswalk, but you don’t see it anywhere in Maya when you try to export.
Usually, this is all you have to do to make Crosswalk available in Maya:
- In Maya, click Window > Settings/Preferences > Plug-in Manager.
- Find the dotXSISceneConverter plug-in and select the Loaded and Auto load check boxes.
- Now when you export, you will see the Autodesk Crosswalk Exporter (.xsi) option in the Files of Type list.
eX-SI 
How much time did it acquire you to write “Crosswalk not
available in Maya | eX-SI”? It has quite a lot of
decent advice. Thank you ,Eve