NA Type in iphone VM greeting

[Let'sgoflying!]

On my landlines I can type in a voice message greetng on the website for callers to hear - how to, on my cellphone?

Iphone SE
10.3.3
Verizon
I get my incoming messages transcribed already

 

[Clark1961]

My liege, upon consulting the great internet you so ably invented for us the answer appears to be the soon to be royal app entitled “youmail”. Although the provenance and veracity of the app developers’ claims remain unproven by your humble servant the feature you so desire is advertised.

-I remain your humble and ever so obedient servant

 

[Let'sgoflying!]

Man, I ran that through google.translate without luck. Anyone?