It is not possible but we do have a feature request to be able to build a Roadmap Planner from an external source, which I believe would meet your requirements:
Please vote on the request and watch it on order to be updated of any changes.
There might be a few alternatives out there for you, if you want to build a roadmap but not be limited to the features in our Roadmap Macro. For example, there's a company called ProductPlan, and they appear to have a way to embed their roadmap within Confluence as well:
I can't confirm if their roadmap feature has a way to generate a roadmap from an Excel file, but it might be worth the look.
Hey there! When you can pack so much information onto a Confluence page, it can be challenging to whittle down what’s most important. Here are a few of our favorite hacks for finding need-to-know i...
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