I think [name_f]Elena[/name_f] is the most common spelling and I aprreciate how visually streamlined it is but the [name_f]Elaina[/name_f] spelling makes the intended pronunciation clearer and I’m a big fan of [name_f]Elaine[/name_f]. I also think the i looks pretty. So idk, I’m between those two options. I think you can spell the nickname however you want, regardless of the full name.