Appium & grid - mixing appium servers (multiple instances)

problem of forwarding a session to specific appium node solved by using “applicationName” capability as discussed in this helpful thread: https://discuss.appium.io/t/device-conflict-while-running-appium-test-using-selenium-grid/2962/11

now the problem is how to populate this capability when doing parallel execution (using cucumber and cucumber-jvm-parallel-plugin).

any ideas?