Google translate, iPhone built-in speak in the screen to unable this feature:
Go to Settings > General > Accessibility > Speech.
Choose any of the following:
Speak Selection: To hear text you’ve selected, tap the Speak button.
Speak Screen: To hear the entire screen, swipe down with two fingers from the top of the screen.
Highlight Content: iPhone can highlight words, sentences, or both as they’re spoken. You can change the highlight color and style.
Typing Feedback: You can configure typing feedback for software and hardware keyboards and choose to have iPhone speak each character, entire words, auto-corrections, auto-capitalizations, and typing predictions.
To hear typing predictions, you also need to go to Settings > General > Keyboards, then turn on Predictive.
Voices: Choose a voice and dialect.
To adjust the speaking rate, drag the Speaking Rate slider.
However, Also this feature automatically built-in in iPhone keyboard you will see microphone icon in right down corner.