Let's talk about emotions.
Le emozioni are "the emotions." That's a true cognate, but the Italian adjective emozionato doesn't have a true cognate.
Let's say you have to talk in front of the class, you have to play a solo in the next student concert, or you're receiving an award. What's the feeling you have?
In English, we would probably use the adjective "nervous." But the adjective we naturally think of in Italian, nervoso, is more about being irritable, in a bad mood. When you are nervous about doing something new, difficult, exciting, the Italian adjective we're looking for is emozionato.
So emozionato can have a somewhat negative connotation in the sense that you try not to let your emotions get the better of you, yet your voice trembles, you get butterflies in your stomach...
"Nervous" is the closest we can get in this sense. It's when your emotions get the better of you in a negative way.
Ho messo il mio vestito migliore per l'occasione e sono in anticipo di un paio di minuti, tanto per essere sicura. Sono molto emozionata.
I put on my best outfit for the occasion and I'm a couple of minutes early, just to be sure. I'm very nervous.
Captions 2-5, Italiano commerciale - Colloquio di lavoro - Part 2Play Caption
The funny thing is that emozionato also means "excited," in other words, a positive emotion. It's not always crystal clear what someone means when they use emozionato, as in the previous example, where Arianna might have been more excited than nervous. We can only guess from the context. In the following example, Adriano may be both nervous and excited, since the baptism of his baby boy is about to take place in a very special chapel in Palermo.
Con tutti i nostri parenti, festeggeremo questo giorno importante nella Cappella Palatina di Palermo. Io sono molto emozionato.
With all our relatives, we'll celebrate this important day in the Palatine Chapel of Palermo. I'm very excited.
Captions 21-23, Adriano - Battesimo di Philip - Part 1Play Caption
Nervoso, on the other hand, often has to do with "stress," an English word that has become ubiquitous in Italian, too.
Caption 17, Marika spiega - Le emozioniPlay Caption
When someone is nervoso, you tiptoe around so they don't snap at you. You don't want to get on their nerves. In fact, Italians use il nervoso as a noun to mean "nerves," as in:
Mi fa venire il nervoso.
He gets on my nerves.
He irritates me.
For more about emotions, see this video.