You can use Pre / Post mode to connect the Nano to H9 I/O 1 and the Tonex to H9 I/O 2. If the preset is set to PRE it will be a preset for the Nano. If set to POST it will be a preset for the Tonex. This will allow to have effects after either of the amp sim pedals.
See page 35 of the user manual: https://downloads.eventide.com/audio/manuals/h9/H9-UserGuide.pdf
