Unable to edit Sharepoint Design Workflows in Sharepoint Designer 2013

We have been migrating to the power automate platform - and doing it in a pace that works for our organisation. We started seeing some issues a few weeks ago with some legacy workflows in Sharepoint. But, when trying to review and see what these legacy workflows are doing, we are unable to open them - which is going to be a pain as we need to see what they actually were doing to replace them with new powerautomate solutions. Is there any way we can access them in the Sharepoint designer? Some workflows appear there, but, workflows that appear to be tied to a list, we are unable to edit/open. Sharepoint just "hyperlinks" to a dead end..

Thanks!