Hi @tamilarasan l,
Unfortunately, it is impossible in SharePoint Online currently. This is by design that only site owners group or one specific email address can receive access requests on a site. We have no way (OOTB or development by yourself) to change this.
I suggest you can share your idea in this portal: https://feedbackportal.microsoft.com/feedback/forum/06735c62-321c-ec11-b6e7-0022481f8472, Microsoft will take your idea into consideration if it is highly voted. Also, you can upvote the similar ideas to yours like this: Access request settings.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
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