My team uses SharePoint Online as our data repository for our NWC workflows. We've realized that Date/Time variables collected in the workflow do not transfer to SharePoint correctly.
I've done some trouble shooting and know that all Date/Time variables within Nintex get converted to UTC. I'm in MST so if I enter 6/7/21 12AM to my form, the workflow variable auto-converts it to 6/7/21 7AM for UTC. When I then send that workflow variable to SharePoint Online it converts the Date/Time variable to 6/6/21 11PM, an hour earlier than the 6/7/21 12AM that I initially entered.
As you can see this is an issue for both having the correct time as well as the correct date listed in SharePoint. This has come up in the Nintex community a couple of times with some workarounds but no real solutions (see links below). Uncovering and fixing the root issue with the connection would make it much easier for my team to fully and accurately use Date/Time variables.
Sorry for the delay in our response. There was an issue with some locations not returning the correct timezone, this should be resolved. If you are still having an issue I would suggest raising with support and they will be able to help investigate.