In LaTeX, it is possible to shift an inline tikpicture with the keyword baseline either by an absolute value or by specifying a coordinate point (as in the example below). It seems that this feature is not supported in LaTeXML.

Here is a minimal example:

\documentclass{article}
\usepackage{tikz}

\begin{document}
Text before
\begin{tikzpicture}[baseline=(baseline point)]
	\coordinate (baseline point) at (0, -1em);
	\draw (0, 0) circle[radius=2em];
\end{tikzpicture}
text after
\end{document}

Crop from the PDF file, pdflatex output:

Crop from the HTML file, latexmlc output: