The latest Super Tucano is a superb aircraft, good range, excellent flying characteristics, great weapons capability, designed for a datalink environment and considerable cheaper than a Typhoon, BUT that doesn't mean it can fulfil the roles allocated to the Typhoon
If it really was that capable why is Brazil currently running the FX2 program? Brazil is a relatively poor country, so this line of thinking should lead us to Super Tucanos, yet the government is planning to spend billions on the Gripen/Rafale/F18 aircraft when Embraer apparently builds the answer to our problem right here in Sao Jose dos Campos. Don't forget that the Typhoon was also considered for FX2 in the early stages.
Barnstormer, Brazil's armed forces are quite capable and reasonably well equipped in all branches, retaining a large cadre of long term professionals, so yes, IF they decided to help they would be a very useful ally. However, in the extremely unlikely event of a second Argentine invasion of the Falklands, Brazil will do what Brazil normally does in these situations, and that is keep out of it.
TTFN