https://espeak.sourceforge.net/editor.html

eSpeak is a compact, open-source formant synthesizer that generates fast, intelligible, albeit robotic-sounding, speech for over 40 languages. Its small, efficient footprint is ideal for screen reading and embedded systems, with a modern, actively maintained fork known as eSpeak NG available. For more details, visit eSpeak SourceForge. eSpeak NG Text-to-Speech – GitHub