Note that strict and warnings are lexical pragmas. It will only apply to the code or file you execute directly, not any included modules. This is a good thing; you don't want to have to fix bugs you introduced to code you didn't write. (This is also why -w and -W are the wrong approach.)
But consider https://metacpan.org/pod/App::MyPerl as it is along similar lines but additionally allows you to apply lexical pragmas to your local modules in lib/.