WRI to DOCMHTML is somewhat odd and rare document conversion, however it should be possible to it directly in Microsoft Word as it should still support the older *.wri documents produced by Windows Write.
Convert Windows Write document file to Microsoft Word MIME HTML document file.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert wri to docmhtml on Windows
One of the most popular word processor program from Microsoft Office suite
Convert from wri file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.