There are channel equipment that can be programmed to send DTMF tones every time you press the PTT and or when you release it. But that depends on the brand and model of the team. You have to see it in the features and functions available in the cane equipment that you have or are going to buy.
The list of equipment registered in RAMATEL (https://enacom.gob.ar/hertz/equipos.csv) are the only ones that can be registered in a legal permit before ENACOM for commercial use.