I was thinking a lot about all Photoshop actions and effect. General conclusion is that you need to know Photoshop to use it in the right way. So I decided to find the solution that will be supereasy and will give really fast and spectacular effects.
Project is a one PSD file (you don't need to import any action, pattern, etc.) and you need to edit one Smart Object to create duotone effect that is ready to go. Drag & Drop and it's ready - simple.
there are 35 different effects included. You can choose which one fit your needs or if you like to work in Photoshop you can edit every part of the design - all layers are editable and well described.
there is also a tutorial that will help you to do it in superquick way,
Project gives you an opportunity to export your ready image as a JPG with few steps.