Hi,
Thanks for the feedback. That's because in the file plugins/editors-xtd/hikashopproduct/hikashopproduct.php we have a check to only display the button for a specific list of components:
if(!in_array($extension, array('com_content', 'com_tz_portfolio', 'com_k2', 'com_jevents')))
return;
We do that to avoid incompatibilities with some 3rd party extensions.
You can change that code to:
if(!in_array($extension, array('com_content', 'com_tz_portfolio', 'com_k2', 'com_jevents', 'com_modules')))
return;
and it will display on the modules manager. We'll add that change on our end.