SEMM is a tool to help simplify the management of mods and mod lists across all of your Space Engineers saves. Currently, it will allow you to take any list of steam workshop URL's, separated by lines, and inject them into an existing Space Engineers save.
In the future it will support checking mod conflicts, exporting mods from existing saves, reorganizing your load order, pulling mods from mod.io, saving new mod lists to load later, and more.
SEMM has currently only been tested on Windows.