I live in Panama, and am aware the country is getting more and more anal about removing its resources (natural life to other countries).
They and some other neighboring countries allow a small number of a species to be taken, without permits, but I don't know the specifics because I don't try to take fish out, I live here.
Th biggest problem I see is getting the fish to live thru the journey.
I have a kit I use just to get them home, and into my tank. the same day they are caught.

Tropical heat is one of the major issues.
A local friend said he was going to the interior to visit family, and offered to collect some from a river next to where he grew up.
I loaned him my battery/car jack operated pump, none of the fish he got survived the in country travel.

He was not an experienced fish keeper, so I was disappointed but not surprised.
And the language barrier didn't help.
When I collect here in Panama, I use a driver I know and trust, and some days are a bust.
Attempted collecting foray to Lago Miraflores
A member here, "newworld" may be able to help with info, he has collected extensively in Mexico and elsewhere