Including the VST in the saving process would be a bad idea, a lot of plugins consist of more files than a single dll or require some sort of activation before use. Everything else is already packed into your projects. The only thing you need on both computers is your VST plugin folder.
Maybe my little tool can help you to manage your VST plugins:
https://forum.renoise.com/t/xrns-listvst-1-3-released/18579