This is a followup question to this question which asked about the possibility of per-site plugin config for Craft 3.
I'm a plugin author and have had a feature request for allowing my plugin to have different settings based on the current site. Looking at the above question, it sounds like this used to be possible in Craft 2:
<?php return [ 'flagName' => [ 'de' => 'Bundesflagge', 'fr' => 'Tricolore', ], ];
This doesn't work in Craft 3, alas (throws an error). I could write something into my plugin's admin area to loop through known sites and output config per-site but this seems like something Craft should be able to do out-of-the-box (especially given the above method used to be valid). Does anyone know if there's a good way to do this in Craft 3?