I have written a shared library in C++ using qt creator and QMake
When I compile my project with MinGW compiler, I need the libraries
Visual C++ Redistributable 2015 x86
Just link standard libraries statically. Your DLL size will increase obviously (I hope it isn't a problem) but not that much (<1 MB).
To do that:
If you use MSVC add /MT to command line (you can find it in project properties window too).
If you use g++ add '--static' .