The customer application is needed that CYW20721 is set Tx power:-13dBm, because it combines with the power amp.
Can CYW20721 be set Tx power:-13dBm?
Sorry, the CYW20721 is not a product supported within the broad market, thus in community. You will want to contact your local Cypress sales/FAE team to discuss the query, and from that point, they can direct you towards documentation and support.
Thanks & Regards,