What are some longer forms for Ness/[name]Nessa[/name]/[name]Nessie[/name]? [name]Agnes[/name] and [name]Vanessa[/name] are the two most common ones, but I’m not terribly fond of either.
[name]TIA[/name] berries!
[name]Nessie[/name] is sooo cute but I also have trouble thinking of any others besides [name]Agnes[/name] and [name]Vanessa[/name]. But I do really love [name]Nessie[/name], adorable.
Renesme…sorry I had to 
[name]Nessie[/name] just reminds me of the [name]Loch[/name] Ness Monster, sorry to spoil it for you but something to consider.
I love [name]Agnes[/name].
The only other option I can think of is [name]Nerissa[/name].
All [name]Nessie[/name] makes me think of is [name]Renesmee[/name] from Twilight…
I love [name]Agnes[/name] but, unfortunately, yes, [name]Nessie[/name] does remind me a lot of the [name]Loch[/name] Ness Monster. I do think it’s adorable, though and I would use it!
A couple more I can think of:
Anastasia – bit of a stretch
Genesis – definitely not my favourite name
Nessa – sounds like a short form of Vanessa, so I wouldn’t use ANOTHER short form with Nessie
Wednesday – worse than Tuesday
[name]Ernestine[/name], which I find both daring and darling.
[name]Tennessee[/name], which is questionable for a girl… though [name]Reese[/name] Witherspoon thought otherwise.
[name]Nessie[/name] also makes me think of the [name]Loch[/name] Ness monster, but I love [name]Nessa[/name]. I read a book with a [name]Glynnis[/name], and she was called [name]Nessa[/name]. I’ve read the Twilight books and I don’t remember her being called [name]Nessie[/name] – not saying she wasn’t, but just that I don’t remember it, so I don’t think it will be people’s first impression.
Nameberry suggests [name]Anastasia[/name]. Nessarose was a character in ‘Wicked’ that could work.
Some other suggestions (some might be a stretch) are:
[name]Agnessa[/name]
[name]Janessa[/name]
[name]Nerissa[/name]
[name]Jenessa[/name]
[name]Narcissa[/name]
[name]Genesis[/name]
[name]Bernessa[/name]
[name]Finesse[/name]
Anesa
[name]Inessa[/name]
[name]Berenice[/name]
[name]Tennessee[/name]
Junissa
[name]Denise[/name]
[name]Eunice[/name]
[name]Venice[/name]
[name]Venus[/name]
[name]Nessia[/name]
Nessya
Nestia
[name]Ernesta[/name]
[name]Ernestine[/name]
[name]Gweness[/name]
[name]Hestia[/name]
Sorry first thing I thought of was [name]Renesmee[/name] from Twilight that’s all I can think of!
I like [name]Inessa[/name] more than [name]Agnes[/name]/[name]Vanessa[/name] (though not as much as [name]Inez[/name])
Not truly related to [name]Agnes[/name], but rather to [name]Anne[/name] - [name]Ana[/name]ïs [ah-nah-ees] is conceivably workable. I find it a bit more euphonious than [name]Agnes[/name] and avoids [name]Aggie[/name], which I detest more than [name]Agnes[/name].
[name]Inessa[/name] is probably easier phonetically though.
Botanical name? [name]Anise[/name]?
[name]Nerissa[/name] was my first though. Then, Nessarose (from Wicked)
Maybe [name]Ines[/name]/[name]Inez[/name]