2 Midi Controllers into Hapax to Control 2 Midi channels at the same time

Hi, I was wondering if I used two midi keyboard into a midi thru box going into the Midi in of my Hapax, if I can play and record midi simultaneously for Hardware Synth 1 out of Midi 1 out and Hardware synth 2 out of Midi channel 2. This might be a dumb question but I’m new with this!

Also, will a midi splitter for the midi outs still be able to control synth individually once I surpass the three midi outs that the Hapax supplies.

Thanks!