If you have upgraded content dabases from different farms and have databases with missing featuers you can use FeatureAdmin. I have enhanced it a little bit 🙂

https://gallery.technet.microsoft.com/office/Feature-Optimized-b379e038

Click LIst All Faulty Features – Can take tike if farm is large.

Export the list for record

Either select one by one of click Delete all.

You should run this a few times to make sure your farm is clean.