That’s what you are after. How often will you take calls like that and how long are the calls?
I use the Phonak version of that every time I have to talk on a “strange” phone. It works. It does make the mic hotter so it is easier to get the sound. You dont have to place it perfectly over the phone speaker.
The fitter will have to set it up for automatic use. Putting it on a manual program is a separate thing.