Hi,
I'm the author of the Robotidy. I missed your questions from this channel because (surprisingly) I wasn't there. But now I joined and I will try to answer your questions.
We opted to not support pipes in Robotidy. Hovewer some people in the community wanted to support it and they added it through PR. To enable pipes you just need to configure --separator option (see --help for details).
All our acceptance tests for transformers uses spaces. That's why it's possible that not all transformers work well with pipes - you can report any issue in our github issue tracker (
https://github.com/MarketSquare/robotframework-tidy/issues) but pipes related issues will have lower priority. I can always take a look if it's something easy to fix /workaround though.