is it possible to add my own URL from where to extract the pdfs?
This would allow me to add my university proxy, thank you
We can use your university’s proxy connection if they use EZproxy. To see how to set that up see here: https://paperpile.com/help#guide-proxy
For non-supported connections, I am afraid we do not have a solution; the PDF downloading process is possibly the most complex part of Paperpile and it would be (more) prone to failure if users supplied potentially arbitrary URLs with which to modify the download URLs.