The process has changed a lot but it is still simple.
There is no option on AWS Console to transfer domains between AWS accounts. The only domain transfer you can do on the console is to bring it from outside the purview of AWS Route53 like GoDaddy.com or Google Domains into AWS.
However, you can do the transfer by yourself using the CLI option. To do this, you must ensure that you have aws-cli 2.09 at least. If yes, then follow the steps using the cli to transfer from 1 AWS account into another one:-
Step 1: Using old account IAM cli credentials, check if you can see your domains or not by aws route53domains list-domains. Then initiate the domain transfer using the below command:-
aws route53domains transfer-domain-to-another-aws-account --domain-name <your domain name> --account-id <destination AWS account id>
Step 2: From above step, you will get an output in a JSON format with operationid and password like:-
{
"OperationId": "c837dj8-5eae-29334-ah72-hs873ns8282",
"Password": "ZKAHD\\WE.4LK\\US"
}
Change that OperationId to DomainName and store it in a new JSON file along with the password like below:-
{
"Password": "ZKAHD\\WE.4LK\\US",
"DomainName": "example.com"
}
Step 3: Execute the last command to accept that domain using the IAM CLI credentials of your destination AWS account or profile like below:-
aws route53domains accept-domain-transfer-from-another-aws-account --cli-input-json file://acceptDomainTransfer.json --profile gsp
Step 4: Done :) Just execute that list-domains command again using new account CLI credentials and you will see your domain moved and listed here:-
aws route53domains list-domains