Whenever you go to uninstall a system app on an Android system, “big brother” warns that some apps are necessary for the system to run correctly, and that other apps may misbehave if you delete this one. Do these dire warnings scare you off from doing anything? They don’t have to.
One of the problems is that such warnings occur whatever system app you may wish to delete; they are not necessarily specific to the selected app. As noted previously (Disabling System Apps on a Smartphone), depending on your actual needs, it may be sufficient to simply disable certain apps. However, if you really do want a given app to go away entirely, firstly disabling it will tell you if your device is going to function without it.
My experience with a Moto G3 smartphone is that the following apps (that I never used) seem safe to delete:
Google Indic Keyboard
Google Japanese Input
Google Korean Input
Google Pinyin Input
Google Play Movies
Google Play Music
Note that not having these apps available doesn’t seem to make any difference to my phone’s operation. But, your mileage may vary! I strongly recommend having a full system backup before you delete anything. (However, all of the above are available in the Play Store so – assuming that your device still boots! – you can always re-install them.)