The best free AI voice over option available is LovoAI, which offers over 500 voices and supports more than 100 languages. While it may take some time to find the right voice to match the content and voice cloning is only available on paid plans, LovoAI is still considered an award-winning AI voice generation tool. Another notable option is Listnr AI Voice Generator, which offers realistic text-to-speech and AI voice with 100 realistic TTS AI voices and multilingual support. It's worth noting that while there may be other free AI voice over options available, these two stand out for their quality and versatility.