How would it affect Brazil's economic, political, and social developments had slavery was abolished from the moment of its independence in 1822 instead in 1888 in OTL? Would it mean more European immigrants in Brazil than in OTL ?
It would't mean that there would't be a Brazil left. The Brazilian independence suceeded because the Portuguese Liberal Courts idiotically tried to turn Brazil into a simple colony again, and because Dom Pedro I promised a conservative secession rather than a radical revolution. The whole Jacobin fright thing was big at the time, and last thing anyone wanted was for Brazil to become a mess. Only chance for him is to declare it only after the Brazilians win, then use the military to keep the unrest down. Good luck not getting deposed.
If Dom Pedro I (in a fit of insanity, I assume) banished slavery, then the major landlords would stop supporting Dom Pedro I and probably defect to the Portuguese as long as they brought slavery back. Lots of soldiers that joined the Brazilians will join the Portuguese instead.
Unless Dom Pedro I can arm a immense army of freedmen and run over the Portuguese with a giant army of freedmen cannon fodder, I can't see this happening. I find that rather improbable, as the Brazilians were rather penyless early in the war so Pedro I can't simply buy lots of guns and ammo and them his mass armies of freedman to fight.
CONCLUSION: Brazil fragmentates into several republics or returns to Status Quo as the Portuguese take over again. Slavery probably returns to most of the country. We might see Brazil or a southern sucessor state losing the Cisplatine province to the United Provinces. Paraguay probably gets annexed without Brazil to support it against Argentina.
Essentially, Brazilscrew, Turbo Argentina and Brazil balkanization or/and Undead Portuguese Empire.
Actually, by 1888 the northeast had few slaves. The province of Ceará abolished slavery in 1884. The northern province of Amazonas in 1885. The National parliament ended it in the entire nation in 1888. Also, Brazil was not the last major nation of what is called the "western civilization" to end slavery. It was either Germany in 1945 or the Soviet Union in the 1970s.
Yeah, most slaves were on the southeast at the time. Dutch Sugar in the Caribbean killed Brazilian Sugar Cane and the slavery it needed to work.