I am looking for a way to aligh contents which are in a cascade in Arbortext Editor, but I would like to aligh them in a row with Arbortext Styler to utilise the space of the page.
Have you considered using a table (or a custom table)? That is probably going to be easiest.
The other feature Styler supports (may need a couple of source edits) is called "side by side", but that's more designed for definition lists and so on.
The easier way is to create a table with 2 columns in order to separate your text. After, use Arbortext Editor to abolish the frame, rowsep and colsep, you should have your text in aligned blocks.