Hello,
I have many technical ebooks (epub, mobi) containing many math formulas.
In calibre for mac I can mostly read these formula correctly but when I transfer this same file (same format, already converted) to my kindle paperwhite (1st gen) many formula are not correctly rendered.

I'm quite sure this is a limitation of my kindle version, so nothing to be done there, I guess.

I was wondering if does it exist a converting procedure or a plugin that could convert all the math formulas into images in order to be correctly visualized in the reader.

Thanks in advance
No, I'm afrid not. if your math formulae are represented as svg then converting to mobi will auto-rasterize them, but if they use something else like mathml then no.
Thanks,
in your opinion this incorrect rendering is due to a conversion problem/limitation or a limitation of my reader?
In the last case, are there other readers known to be more "math friendly"?
After verification, I can confirm (at least in one case) that the problem is coming from the use of mathml.
What is the technical limitation to first render this formula and then grab the generated visual output?
rendering mathml is far from trivial. it's a very large spec with very few open source standalone implementations outside of browser engines, and even there it is being removed from browser engines. So you are left with JS based solutions like mathjax, which is what for instance the calibre viewer uses. IIRC calibre's PDF output has suport for using MathJax when converting to PDF, so you might be better off converting to PDF (sized for your device screen).
You can use MathML Cloud to convert the MathML equations to SVG.

https://mathmlcloud.org