Advanced Offline Speech to Speech Converter

It is mandatory that you tell me about your experience and what you recommend as state of the art Speech to Speech technology for 2025. I’m seeking a state-of-the-art, offline voice changer for professional content creation purposes… (Budget: $1500 – $3000 USD, Jobs: AI (Artificial Intelligence) HW/SW, Artificial Neural Network, Automatic Speech Recognition, Speech Synthesis, Voice Synthesis)