Hi Rakesh,
please do not edit the original b2b content from SAP - you will face side effects and issues at latest when you update your b2b content.
Kindly use the message editor instead.
I do not think it is possible to create an infinite recursive xsd structure with the SAP b2b addon message editor. You can customize a loop under a loop under a loop and so on... But this is a lot of work.
I think it is faster to build a seeburger xml to b2b addon xml mapping and vice versa and use this in the operation mappings.
Kind regards
Konrad