I want to know if there is a way to control the Virtual switch settings (at least enable/disable) from node red, and if yes how can i achieve this ? - picture for explanation of what i understand by Virtual Switch 
Describe your system a little more and what you want to use it for … There may be other possible solutions.
Normally you do not have access to the wizards or virtual switches of the Multi with Nodered … these are stored in the Multi itself and are also controlled from here.
Have you ever downloaded the “Modbus TCP Register List”? It contains all the registers that you can access … read and / or write.
As far as i know you cant. The base programming is not designed for that (except for those that can be overidden through the gx normally)
Wondering to what end though, when you can disable it and build an entire ac ignore function in node red?
so the system is a pretty simple one , with a multiplus 2 and a charger. they cannot inject to the grid , so currently they have this virtual switch set up cu completly isolate the victron from the grid. There is no possibility of adding an external contactor to physically isolate the multiplus from the grid. The use case for disabling the virtual switch is when for example there is a hurricane warning and you want to have your batteries charged even if there is no sun.
Is this possible to build a logic in node red to function like a virtual switch ?
Yes.
Basically you are switching the inverter mode and grid connected based on some conditons like load or battery voltage.
If you aren’t node red savvy then an easier way is with the generator start stop on the gx wired to the temp sensor (which will have an assistant that switches the primary relay based kn whether it is open or closed.)
Then you can manually connect from there or have it based on load and state of charge.
So bassically from the venus os node i select inverter mode? And grid tie mode? So i need the multiplus to be completely isolated from the grid, so no spill in the grid happens as it does when you set zero feed in the ess settings. Would that be possible without any extra contactors?
Yes as it drives the internal contactor for normal grid connect.