I don't think you actually could use tones instead of pulse on a rotary phone.
Well, technically you could, if you took everything out and replaced all the guts to send the right pulse based on the timing of the rotation, of course. Or if you put some kind of translator between it and the network.
Rotary phones were fun because what they did was basically hang up shortly for each digit. So it was easy to dial a number just from the hook, even when there was one of those silly little padlocks on the dial.
It used to work at least here in the Netherlands, when you send a sms to a landline, the phone company has a tts service that reads texts like: “incoming text from zero six one… (etc) with the following text: ok boomer” and repeating that twice.
Used to be a really mechanical voice, but I’ve not had a landline in at least ten years.