I’m not sure if this is possible. Where do you envision the microphone signal being output to? If the MixingLink is in your switcher loop, it would be output with your guitar signal, and that is probably not desired. I’m assuming you’d want the microphone output on its own line to a PA or separate speaker.
A simpler setup would be using Path 1 in the switcher for your guitar, and Path 2 with the MixingLink for your vocals, . This configuration is demonstrated here: https://cdn.eventideaudio.com/manuals/h90/1.3.0/content/setup/mixinglink.html
With this configuration, you could use both Presets on Path 1 or 2, or one Preset on either Path.
