General Brazilian
estressando / dando estresse
Most common usage in everyday Brazilian Portuguese
Rio de Janeiro
estressando / enchendo o saco
More colloquial/slang usage in Rio
São Paulo
estressando / chatoando
Common usage in São Paulo, sometimes with 'chatoando' for annoying sense
Portugal
a causar stress / enfatizando
European Portuguese prefers 'stress' as loanword or 'realçar' for emphasizing