Real Life Characters

It takes time and money to create files of "real life looking characters with different poses." I don't know any good source that would give them away for free.

The more specific one's request is for certain character traits and expressions, the more likely it is that filling the request will require licensing characters from a company that focuses on that service, buying images from a stock photo agency, or even paying for a custom photo shoot. Nowadays, it may also be possible to get the images you want using AI.

I would personally use AI for that 🤖. 
Describe the character what your are looking for as detailed as you can, ask for neutral pose and face expression, transparent background.
When you are satisfied with the character appearance, start creating different poses and face expressions (also describe the pose and emotion in details), using the "neutral" character as a reference for each image.  
Good luck! 

Have you see our catalog of free, downloadable characters? Many of these are illustrated, but you may find some photo-realistic characters you can use! What kinds of photo-realistic characters are you looking for, specifically?