Greetings and welcome.
If I understand your question, the basic answer is yes, you can feed “trigger notes” to Scaler and Scaler will respond with the chords or, if you have Performances enabled, the performance playback.
For this to occur, you need to be sure you have a Bind button enabled in the section you are using.
Now, when that track plays, Scaler will use any notes on the track to trigger what ever settings you have enabled in Scaler. Understanding what Scaler setting is enabled when you playback a track, is part of keeping things straight in your head.
FWIW, I’d start with a simple, empty project and just do the basics 1st. 1 track, and 1 instance of Scaler.
As for using Scaler as a Midi FX, you are correct that S1 does not “support” midi FX in the same way as some other DAWs. However, it is an easy routing setup in S1 and part of my standard Scaler template…
Here is a post on routing Scaler in Studio One 5.5 (should be the same as 6+)