This is my experience.
I was always told that Jehovah's Witnesses are the same all over the world. They are not!!
It makes sense to me now that people are what make a congregation what it is, not doctrines. Yes the doctrines are pretty much the same but the people from different countries and cultures make the congregation what it is.
The major differences I found were Spanish witnesses do not have a problem with swearing. Even the c word is acceptable. That was a shock the first time I heard it from a brother, I can tell you! He called his wife one.
Dress code was much more lax. Brothers would wear sandals with socks (yuck) if they were not on the platform. Short sleeve shirts and no jackets were also allowed. No ties on field service! That was strange. Much more coffee and shopping whilst on field service.
Parties were fantastic. Lots of provocative dancing, salsa style but would not have been tolerated here in UK.
Disfellowshipping still happened but not the shunning. They still associated with us away from the KH.
Gossip was rife. No secrets at all. Lol
Very loud disagreements amongst bros and sisters but that is the Spanish way. Loud, short and over very quickly.
Sisters were able to dress very minimalistically when it was hot. Sometimes visitors were surprised at how short the skirts were and shoulders were always bare and undergarments invariably showed. Quite often the under garments were a bikini as we would be going to a pool party or the beach straight after.
UK congs are formal and stuffy and the people are cold compared to the Spanish.