Lyle is one of the few names it seems anymore that doesn't have an obvious feminine form.
(Although Nameberry is trying to say it's "cool for a girl" No it's not, fuck you Nameberry)
Anyway.
Lila
Lyla (variant of Leila)
Lynn
Flow wise, all of my suggested names that are similar to Lyle sound like a continuation of Emma as opposed to two separate names. I don't think it's that big of a deal since you are specifcally doing this to honor your grandpa. But if that bothers you, look to his middle name or a nickname for possibilities.( My one grandpa was Wilbur, and everyone called him Web, so my nephew is Firstname Web Lastname)
Emma has become so popular over the last 10 years and is still on the top ten list... not sure if that matters to you or not. Personally, I think Lila/Lyla is much nicer. Why not consider it instead of Emma?
Lila/Lyla has the same end sound as Emma and it has a feminine twist to your Grandpa's name, Lyle. Love honor names!
Lyla (or various spellings) is definitely the most feminine version of lyle that I can think of. I know it might have personal meaning and wanting to honour a family member is great, but definitely use the feminine version ^^
Re: Female Versions of the name Lyle (middle name)