How can I convert Amazon Transcribe json response to a caption format (srt, webvvt, etc)?

You probably would have found a way to do that or created a script. I also tried finding some ready made solution so ended up writing some JavaScript code to generate SRT from the JSON output of Amazon Transcribe.

https://www.yash.info/aws-srt-creator.htm

I am breaking sentences at period (.). It's a standalone HTML file. Feels free to download and modify as required.

I've used this python script from github and it formats really nicely into docx format. The output even includes scatterplots of the confidence levels of words as well as changing the colors to lower confidence words.

https://github.com/kibaffo33/aws_transcribe_to_docx

This worked really well for me, but I think you could have this go to html fairly simply if you wanted to alter the python script.