Not sure if you have tried/heard of Whisper. It automatically transcribes audio, I use it for meetings/lectures that don’t come with Closed Captioning, it supports audio/video files and a few languages. I had tried a few solutions with mixed results (e.g. Google is slow, many places limit lengths/sizes), IBM is supposed to be the best free/low cost cloud model but they would never approve my accounts. In the end locally with whisper in an Anaconda/Python environment was best cheap option for me.