I’m posting this as I found it useful and thought some of you might as well. Recently I needed to move several lists into Reminders. I had emailed the lists to myself from a different app, but could not figure out how to paste them into Reminders as a list. Everything I tried ended up with a single Reminder item containing the entire list 
A bit of internet searching turned up this article which has the answer: basically you have to paste into Notes, and if you copy from Notes into Reminders it remains as a list.
Pretty crazy there’s no other way!