I tried my best to write this code and hopefully it will be helpful.
These links helped me to write this code:
https://www.latex-tables.com/
Bullet point list inside of a table
https://www.overleaf.com/learn/latex/Lists
The code:
\documentclass{article}
\usepackage{caption}
\captionsetup[table]{}
\usepackage{multirow}
\usepackage[utf8]{inputenc}
\usepackage{amssymb}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\begin{table}
\centering
\begin{tabular}{ll|ll}
%\cline{1-3}
& Column 1 & Column 2 \\
\cline{1-3}
Type 1 & \multirow{2}{*}{\begin{tabular}[c]{p{0.4\textwidth} p{.03\textwidth} p{0.4\textwidth}}
Category1
\begin{itemize}
\item Item 1
\item Item 2 Item 2 Item 2 \newline Item 2 Item 2
\end{itemize}
\\\\Category2
\begin{itemize}
\item Item 1 Item 1 Item 1 \newline Item 1 Item 1
\item Item 2
\end{itemize}
\end{tabular}}
& \begin{tabular}[c]{p{0.4\textwidth} p{.03\textwidth} p{0.4\textwidth}}
\begin{itemize}
\item Diff1
\item Diff2
\item Diff3
\end{itemize}
\end{tabular} \\
\cline{1-1}\cline{3-3}
Type 2 & & \begin{tabular}[c]{p{0.4\textwidth} p{.03\textwidth} p{0.4\textwidth}}
\begin{itemize}
\item Diff4
\item Diff5 Diff5 Diff5 Diff5 \newline Diff5 Diff5
\item Diff6
\end{itemize}
\end{tabular} & \\
& &
& \\
%\cline{1-3}
\end{tabular}
\end{table}
\end{document}
.
.
The result:

Maybe for the formatting, you can play with the spacing, font size .. etc. Or you can use some commands to resize the table.
Regards,
\multirow. Regarding the lists, you might be interested in this solution – leandriis Jul 22 '19 at 18:20