You actually cannot convert MS Access .accde files to anything else, much like the previously used .mde files that were used for same purpose. ACCDE format is designed to be view only executable that allow users to access and view the database, but not edit it. There is really no way how to reverse the process unless you have access to the original database.
Convert Microsoft Access 2007/2010 compiled execute only file to Microsoft Access compiled database (application).
We found 2 software records in the database related to .accde to .mde file format conversion.
Microsoft Windows software - convert accde to mde on Windows
A relational database management system from Microsoft Office
Convert from accde file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned accde to mde. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert accde to mde on OS X
A database viewer