Use symbols from **bartel-chess-fonts** in Overleaf

You can use the fonts only with low-level commands, or through the diagram package https://www.ctan.org/pkg/chess-problem-diagrams. There is no nfss-support for LaTeX.

So normally something like fontchessfont=pkelch12 {chessfont char99} is needed, you can find out the char number by looking at the font table below. I had to tweak an internal command as the fonts have a bit curious design size.

The fonts are bitmaps.

documentclass{article}
usepackage{fonttable}
begin{document}

fontchessfont=pkelch12 {chessfont char99} 

makeatletter

% to get around the curious design size in the fonts:
renewcommand*{f@tstartfont}{%
  @tempdima=f@size pt
  fontf@ttestfont=f@tfontnamespace at 100ptrelax %force size ...
  f@ttestfont f@tsetbaselineskip
  ifdimfontdimen6f@ttestfont<10ptrelax
    rightskip=0pt plus 20ptrelax
  else
    rightskip=0pt plus 2emrelax
  fi
  spaceskip=fontdimen2f@ttestfont % 
  xspaceskip=fontdimen2f@ttestfont
  advancexspaceskip byfontdimen7f@ttestfont
}




fonttable{pkelch12}
%fonttable{fselch12}


end{document}