You can simply repack RAR archives to 7-ZIP when you extract the original archive and compress in again to 7z archive.
Convert WinRAR RAR compressed archive to 7-ZIP compressed 7z archive file.
We found 11 software records in the database related to .rar to .7z file format conversion.
Microsoft Windows software - convert rar to 7z on Windows
Popular open source file archiver with a high compression ratio
Convert from rar 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 rar to 7z. 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.
One of the many available file compression utilities
One of the oldest and most popular shareware file archiver and data compression utility
A free open source archive utility
Apple macOS / Mac OS X software - convert rar to 7z on OS X
Ma version of a free compression utility
A compression utility for OS X
A compression utility for Mac
Mac version of the popular utility
A backup and archive utility
Full-featured compressed archives manager
Linux/Unix software - convert rar to 7z on Linux
A Linux application used as frontend for popular compression tools