In theory, yes - but it may not be a simple "point and click" solution. Atlassian provide an open sourced tool for migration, but they don't support it:
and here are the notes about MediaWiki specifically https://migrations.atlassian.net/wiki/display/UWC/UWC+Mediawiki+Notes
I'm assuming if you can export MediaWiki into the right format for Confluence Cloud, you can then import.
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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