Ιf you asked a multilingual friend which language they find more emotional, the answer would usually be their mother tongue – the one they used while growing up and probably still use at home. This does not mean they are incapable of expressing emotion in another language, but there is a clear link between first languages and stronger emotional expression.
This has a lot to do with where and how we learn a language. Our first language, which linguists call L1, is usually acquired in the emotionally charged settings of childhood and family. Second languages, known as L2, are often learned in more neutral contexts, such as schools and institutions, making them less emotionally intense.