"Hey", /ˈheɪ/, has a dipthong /eɪ/, so é is precisely the first half of that dipthong. It may feel like it's between the “e” in “bet” and “ee” in “see”, but using the dipthong you don't have to guess it.
That’s why they always have such predictable accents in another language.
Dr Geoff Lindsey on youtube:
short version: https://youtube.com/shorts/GF1gIaxnULc?si=d4jFC-rLOC5dww-8
long version: https://youtu.be/GNpbv7hJf6c?si=xNz1UjeLY0Ch9eDv&t=366