This question seems to touch on the apparent fact that NIST SP 800-90B is not suitable for estimating entropy produced by sources that are not uniform, despite being IID or non-IID. It also seems that most phenomena for producing entropy are not uniform. If that's indeed right, then naturally one wonders what adequate tools are available for estimating entropy?
Clarification. The question is asking for tools like NIST SP 800-90B. What programs are out there that are ready to use, hopefully with a publication to introduce it? It seems only NIST SP 800-90B is available.