twig call macro in different folder
You can call the macro by:


In the same twig Using _self:
From Documentation:


  It's possible to place the macro within the same twig from which you call it. The _self context is used in this case...



{{ _self.crop_text(text, len) }}


From External File using import :
Like the following:
Just move your croptext.twig into yourtheme/templates folder and then you can use the following call in any twig:


{% import '@yourtheme/croptext.twig' as cropText %}

For more information take a look at Macros in Twig Templates documentation.