can we do the same static routes for the same CIDR in 2 different routing table in the same transit gateway ?

Hi, Understanding what you are trying to achieve will help getting you to the right answer. If you have multiple Transit Routing Tables, you will have different TGW Attachments associated with each route table. You can have a static Route in each Routing Table for the same CIDR with the same destination. Such use is helpful in the below use-cases:

• Segmentation. Different VPC where some sort of isolation is required but they still need to access resources from shared VPC.
• Engineering traffic to allow the use of Egress VPC or Inspect VPC.
• Decentralized Architecture

If this isn't helpful, please share what problem you are trying to solve to be able to have a more a problem driven feedback.

Yes, you can have the same static route in 2 different transit gateway route tables which are associated with the same transit gateway.

Please note that transit gateway attachment would only use one Transit gateway route table to forward traffic through the Transit gateway. So, as AmeO has posted, based on the use case you can decide whether doing this would actually be of value or not for your architecture.