at o365 workflow, click on the Variable Icon: 

1. Unable to sort Variables by any of the headings; the list displays variables as they were entered (with no other options); was able to sort by Name & Type on-premise which helps organize lots!

2. Unable to delete multiple variables at once; must use the garbage Icon, 1 at a time to delete; cannot select multiple vars, then delete all.

3. Edit variables is weird:  can only change 1 character, then kicks you to the end of name

any other experience with this? Not very user-friendly.  see my User Voice at:  https://nintex.uservoice.com/forums/218291-3-nintex-workflow-for-office-365/suggestions/40526167-sortable-variables-at-the-variable-icon

*worked on-premise

thanks, sue