this one "é" produces a shord /e/ like when you say "écoute" you don't need to open ur mouth that much. But this one "è" produces a long /e/ so even in phonetic its symbole changes to long one. Like in the word "mère" you pronounce it long. Hope it s helpful. :)

É sounds like "ay" or the american sound for the letter "a" - like in the word "game". The mouth is relaxed. È is said with a very wide mouth and is not as pleasant a sound as É. The best "è" sound in English are in the word "jet" and "message". E without accent sounds more like "uh" or "er"in English. It will take time for your ears to tune in those sounds. That's perfectly normal. You need to be able to hear the difference before been able to hit the right note.

É and è are two different ways of pronunciation (quite difficult to distinguish when you're not used to). É is pronunced as "eternal" (first "e") È is pronunced as "est"