Source: https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-sso.html
To manually add AWS SSO support to a named profile, you must add the following keys and values to the profile definition in the file ~/.aws/config (Linux or macOS) or %USERPROFILE%/.aws/config (Windows).
sso_start_url
The URL that points to the organization's AWS SSO user portal.
sso_start_url = https://my-sso-portal.awsapps.com/start
sso_region
The AWS Region that contains the AWS SSO portal host. This is separate from, and can be a different region than the default CLI region parameter.
sso_region = us_west-2
sso_account_id
The AWS account ID that contains the IAM role that you want to use with this profile.
sso_account_id = 123456789011
sso_role_name
The name of the IAM role that defines the user's permissions when using this profile.
sso_role_name = ReadAccess
The presence of these keys identify this profile as one that uses AWS SSO to authenticate the user.
You can also include any other keys and values that are valid in the .aws/config file, such as region, output, or s3. However, you can't include any credential related values, such as role_arn or aws_secret_access_key. If you do, the AWS CLI produces an error.
So a typical AWS SSO profile in .aws/config might look similar to the following example.
[profile my-dev-profile]
sso_start_url = https://my-sso-portal.awsapps.com/start
sso_region = us-east-1
sso_account_id = 123456789011
sso_role_name = readOnly
region = us-west-2
output = json```