This repository contains a Powershell module that downloads nuget (and chocolatey) packages as nupkg files from a feed including their dependencies
choco install NupkgDownloader
Once installed, run the command as follows (e.g. this will download fooPackage version 1.2.3 from the chocolatey community feed to c:\temp\install, along with all of its dependencies):
Download-Nupkg fooPackage -Version 1.2.3 -OutputDirectory c:\temp\install -Source "https://community.chocolatey.org/api/v2/"