Yes. Both PCs are running the NodeRed dashboard in a browser.
It can be a normal dashboard with normal packages like graphs.
The NodeRed server is running on both PCs like we start it in terminal or cmd and the dashboard in the browser.
Its difficult to explain it for me because my English it not so good. I am very sorry about that. But I told you I want to take a file from my PC upload it with NodeRed and the other PC want it tu download it.
I open this flow in NodeRed now but I can't finde where can I choose my file which I want to upload or where I must change something to select my file.
So you have two node-red servers, one on each PC. and want to transfer a file from one pc to the other. I think you will have to setup some form of file sharing between the two machines.
You could send it via http or if not too big via mqtt. It might be simpler just to enable file sharing between the machines though.
I presume the two machines are both on the local network.
TCP is also an option, but i would prefer something like SCP SMB or even FTP.
Even these protocols could be implemented to work flawlessly via node-red and even built with dashboard...