LOOKING BACK: The US Coast Guard cutter USCGC Escanaba (WMEC 907), Brazlian Navy ship BNS Bosisio (F 48) and Argentinian navy ship ARA Almirante Brown (D-10) move into formation for a photo exercise during the Atlantic phase of UNITAS 52 on May 4, 2011. The formation included a total of ten ships from the US, Brazil, Mexico and Argentina. (Photo: US Navy/Mass Communication Specialist 1st Class Steve Smith)
The Navy League’s on line magazine, Seapower, reports on the upcoming 63rd UNITAS exercise,
RIO DE JANEIRO, Brazil — Navy and Marine forces are set to arrive in Rio de Janeiro in support of UNITAS LXIII, the world’s longest-running multinational maritime exercise scheduled to take place Sept. 8-22, the U.S. Naval Forces Southern Command / U.S. 4th Fleet said in a Sept. 1 release.
This year’s exercise is hosted by the Brazilian navy and will included 20 participating nations, 19 ships, one submarine, 21 aircraft, accounting for approximately 5,500 total military personnel that will conduct operations principally off the coast of Rio de Janeiro.
USCG Pacific Area Tactical Law Enforcement Team (PAC AREA TACLET) will be there, but apparently no other Coast Guard units.
Notably, Argentina is not participating.
Chuck Hill's CG Blog 
Good description of the exercise here: https://seawaves.com/2022/09/20/18-navies-in-brazil-for-exercise-unitas-lxiii/
Sounds like they have a particular portion of the exercise that would have been appropriate for the Coast Guard,
““In this edition, there will be a specific task unit focused on maritime security. These exercises will be carried out by the Patrol Vessels of the Cameroon Navy, from Namibia, as well as by the British and Brazilian Patrol Vessels”, said Admiral Cardoso.”
It’s not really clear what you are saying here. Focusing on maritime security where?
That is not my statement, that is a quote from the description of the exercise. I don’t have any additonal information not contained in the article.
The wrap up report did say, “Events included: … illegal drug trafficking training… and maritime interdiction operations.
Exercise wrap up https://seapowermagazine.org/unitas-concludes-after-successful-exercise/