I'm not aware of how you could do something like this without writing some custom java. The best I can think of (which would be a terrible user experience IMO) is to have a custom object in Maximo where you would store the URLs and any other metadata you wanted to capture about that link. From there a user could copy & paste the link in their browser. There's not a way that I'm aware of to make it function like a launch in context where it'd open in a new browser tab. It'll always just open the record in the application.
I don't know how long it would take to build a start center portlet for a use case like this, but I don't think I'd go through the effort personally. I'd rather spend the time working with an external dashboard solution that would support that and some other scenarios that don't work well in the Maximo side. For example, apps like Power BI/Tableau allow you to provide in context filters that update the rest of the dashboard. So I could select CM work for example and all the portlets would be filtered to just that use case. It allows you to drill in deeper to your data in ways that you can't do with Maximo Start Centers. And some of the functionality inside Maximo (such as clicking a result set to open that record in Maximo) is pretty easy to do with query parameters.