Use VoWifi but not VoLTE

[dynamitten]

Hi.

My Telco supports both VoWifi and VoLTE. VoWifi are very usefull at home where the mobile signal are extremely poor.
To enable VoWifi I also have to enable VoLTE. But when I am outside my home and the conversation goes through LTE, then the quality are pretty bad.
Does anyone know a simple way to disable VoLTE but keep VoWifi on a Samsung S7 Edge? App maybe?

Going to Settings - mobile network - disable VoLTE when outside my home and then remember to enable it again when coming home is annoying.
And why does those two different technologies stick together on a Samsung device?

Thanks
Torsten