They implemented a built in visual diff tool that diffs the graphs and properties side by side and integrates with any of the supported source control plugins.

They implemented a built in visual diff tool that diffs the graphs and properties side by side and integrates with any of the supported source control plugins. Merging has to be done manually though, so most teams use source control locks like for art assets. There are several ways to split blueprints into more files to result in less locks.