Hello @Mohammed Thahif BK ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you are trying to implement vWAN for disaster recovery and would like to connect the virtual hubs in vWANs deployed in different subscriptions via hub-to-hub connectivity.
You can use Virtual WAN to connect a VNet to a virtual hub in a different subscription/tenant but connecting a Hub in VWAN A to a Hub in VWAN B via the normal VWAN hub to hub mechanism is not currently supported today.
Doc for connecting cross-tenant VNets to a Virtual Wan hub : https://video2.skills-academy.com/en-us/azure/virtual-wan/cross-tenant-vnet
If you wish you may also leave your feedback in the below forum requesting this feature. All the feedback you share in these forums will be monitored and reviewed by the Microsoft engineering teams responsible for building Azure.
https://feedback.azure.com/d365community/forum/8ae9bf04-8326-ec11-b6e6-000d3a4f0789
The only workaround I can think of is to connect vHub in VWAN A to vHub B using VPN gateway of the Virtual Hubs.
Refer : https://video2.skills-academy.com/en-us/azure/virtual-wan/connect-virtual-network-gateway-vwan
Kindly let us know if the above helps or you need further assistance on this issue.
----------------------------------------------------------------------------------------------------------------
Please "Accept the answer" if the information helped you. This will help us and others in the community as well.