Is there a way to move a document from one site to another site collection? Will it be possible to use web service calls and not sure what methods to use? any help will be appreciated
Nintex workflow offers several actions out of the box that allows you to manage documents, however moving them across site collections is a bit tricky with permissions etc. You could look at rest end points for accessing the document, storing it locally and then loading it somewhere else. The other option is using the content hub to move documents around. This is possible to do, just may not be as easy or straightforward.