An experimental hackety hack to export HTML from LaTeX on Overleaf, using make4ht:
Math is exported as MathML and will be rendered using MathJax;
EPS and PDF graphics are converted to PNG;
JPG and PNG graphics are used as-is;
TikZ drawings are exported as SVG.
In this sample set-up, the HTML export will only be triggered if the project is set to compile with pdfLaTeX. (I haven't had time to test with XeLaTeX an LuaLaTeX properly) It'll take longer than usual to compile your project; so probably a good idea to only add the latexmkrc file that triggers the HTML export when you're quite down with writing.
You can download the generated files using the steps described here.
make4ht does not work well with authblk, fontspec and possibly other packages. This is an experimental hackety hack!