Hi @manisha594391,
It is not available as configuration to amend the default view.
Logic for Inbox search page/results view is available at
/libs/granite/ui/components/shell/omnisearch/searchresults/searchresults.jsp where view is retrieved from cookie named shell.omnisearch.results.layoutId
Since Omnisearch node(/libs/granite/ui/components/shell/omnisearch) is greyed/has mixin with granite:InternalArea, "Overlay Node" is disabled.