I think you can have the scripts talk to each other through Elixir via the BEAM/OTP approach: for each script you will have a GenServer module that manages it in a separate process. Call this module MyApp.ScriptServer and put "use GenServer" at the top of the file. This GenServer process will have a client API, which you can write, which will be how you interact with your script. In the BEAM programming model, processes communicate by sending messages to each other's mailbox, so you set up some logic for this and maybe have another module called MyApp.ScriptCoordinationServer that manages some global state.
This is just my amateur guess -- I'd be happy to hear an Elixir/BEAM/OTP expert chime in.
