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[name_f]Cybele[/name_f] - “mother of all gods” according to Namberry
[name_f]Madrona[/name_f] - “mother”
[name_u]Demeter[/name_u]- “earth mother”
This is a hard one, to find names that mean mother or matriarch, have you considered looking up what your mother’s name means, and then finding a name that also means the same thing?
[name_m]Say[/name_m] if your mother’s name is [name_f]Margaret[/name_f], and [name_f]Margaret[/name_f] means “pearl”! You could name your child [name_f]Pearl[/name_f], or [name_f]Gretta[/name_f], or [name_f]Megan[/name_f], or [name_f]Marjorie[/name_f], [name_f]Margot[/name_f], [name_f]Peggy[/name_f]…Your mother’s name should mean something, and should have something similar! Or, like the name [name_f]Margaret[/name_f], have lots of diminutives that really don’t seem that much like the original name, but are still derived from it!
[name_f]Hope[/name_f] this helps! 
What was your mother’s name? Dated names aren’t always impossible; [name_f]Karen[/name_f] becomes [name_u]Kieran[/name_u], [name_f]Brenda[/name_f] becomes [name_m]Brendan[/name_m], [name_f]Linda[/name_f] becomes [name_u]Linden[/name_u]. You can always use [name_f]Lily[/name_f], the meaning of [name_f]Susanna[/name_f] - and therefore [name_f]Sue[/name_f] - or any of its variants: [name_f]Liliana[/name_f], [name_f]Liliane[/name_f], [name_f]Lilia[/name_f], etc. These showed up in my search as meaning mother:
[name_u]Amari[/name_u]
Maylis or Maëlys, possibly from mair “mother” and lys “lily”
[name_f]Candace[/name_f]
Thank you for the in depth responses! Her name was [name_f]Sharon[/name_f], which means “plain” - kind of a dead end in my mind, but I’m open to creativity.
Well… let’s see! [name_f]Eve[/name_f] is sometimes viewed as the mother of all in the [name_m]Christian[/name_m] faith, so [name_f]Eve[/name_f] could work! [name_f]Abra[/name_f] (feminine form of [name_m]Abraham[/name_m]) means mother of multitudes.
Other suggestions:
Akna - [name_f]Goddess[/name_f] of motherhood in Mayan mythology
[name_f]Cybil[/name_f] - meaning “great mother of the gods”
[name_f]Candace[/name_f] - “[name_f]Queen[/name_f] mother”
Based on [name_f]Sharon[/name_f]:
[name_u]Blair[/name_u] - same meaning - ‘a plain or flat area’
[name_u]Shae[/name_u]
[name_f]Erin[/name_f] - ‘[name_f]Erin[/name_f]’ is almost in the name [name_f]Sharon[/name_f] when spoken
[name_f]Nora/name_f - Last four (five) letters of [name_f]Sharon[/name_f] backward
Anything strike your fancy? Good luck
I think [name_f]Medora[/name_f] comes from ‘‘mother’s gift’’.
Some others from a bit of research;
[name_f]Emese[/name_f]
[name_f]Mari[/name_f]
[name_f]Sharon[/name_f] is a place name from the bible so maybe another could work, like [name_f]Bethany[/name_f], [name_f]Galilee[/name_f], [name_m]Israel[/name_m], [name_f]Samaria[/name_f], [name_u]Shiloh[/name_u].
[name_f]Randa[/name_f] and [name_f]Sahara[/name_f] have similar meanings to [name_f]Sharon[/name_f] and also share similar letters. Other similar lettered / similar sounding names;
[name_f]Nora[/name_f], [name_f]Sora[/name_f], [name_f]Rhona[/name_f]/[name_f]Rona[/name_f] and [name_f]Rosa[/name_f]
[name_f]Sharai[/name_f]/[name_f]Sarai[/name_f]
[name_f]Shari[/name_f]/[name_f]Sari[/name_f]
[name_u]Sasha[/name_u]
[name_f]Sian[/name_f], Sharn
[name_f]Ronja[/name_f], [name_f]Ronia[/name_f]
[name_f]Roxanne[/name_f]
[name_f]Charlotte[/name_f]
It’s me again! I like [name_f]Sharon[/name_f], it’s sweet Here’s a little list!
[name_f]Savannah[/name_f] - [name_f]Sharon[/name_f] means ‘a plain’, and the [name_f]Savannah[/name_f] is a grassland
[name_f]Cheri[/name_f]
[name_f]Cher[/name_f]
[name_u]Blair[/name_u] - dweller on the plain
[name_f]Sharona[/name_f]
[name_f]Sharene[/name_f]
[name_f]Sharee[/name_f]
[name_f]Hailey[/name_f] (and all its variations) - meaning meadow or field, close enough to plain haha
[name_f]Meadow[/name_f] (close enough to plain haha! and pretty)
[name_u]Prairie[/name_u]
[name_u]Cheyenne[/name_u]
[name_f]Hope[/name_f] this helps! My personal favorites are [name_u]Blair[/name_u] and [name_u]Cheyenne[/name_u]!
I’ve heard of [name_f]Rose[/name_f] being a nice nod to [name_f]Sharon[/name_f] from the “[name_f]Rose[/name_f] of [name_f]Sharon[/name_f]” connection. I like the suggestions of [name_f]Eve[/name_f] and [name_f]Erin[/name_f]! Also:
[name_u]Shalom[/name_u]
[name_u]Seren[/name_u]
[name_f]Maren[/name_f] or [name_f]Marin[/name_f]
[name_m]Theron[/name_m] {b}
[name_m]Heron[/name_m] {middle}
If her name was [name_f]Sharon[/name_f], what about [name_f]Rose[/name_f], [name_f]Savannah[/name_f], [name_u]Leigh[/name_u], [name_u]Ainsley[/name_u], or [name_f]Meadow[/name_f]? I really love the idea of [name_f]Meadow[/name_f] as a middle name. The rest could be firsts (also love [name_f]Meadow[/name_f] as a first but I think it depends on your taste). [name_u]Ainsley[/name_u] means “one’s own meadow” which would be very appropriate for your situation. Good luck!
[name_f]Amma[/name_f] is an anagram of Mama.
[name_f]Emese[/name_f], [name_f]Jarita[/name_f], [name_f]Maia[/name_f], [name_f]Medrona[/name_f] and [name_f]Moa[/name_f] mean “mother”.
[name_f]Neith[/name_f] means “divine mother”.
[name_m]Quigley[/name_m] means “from the mother’s side”.
[name_f]Cybele[/name_f] means “mother of all gods”.
[name_u]Demeter[/name_u] means “earth mother”.
[name_f]Gaia[/name_f] means “earth mother”.
[name_f]Iyabo[/name_f] means “mother returned”.
[name_f]Medora[/name_f] means “mother’s gift”.
There’s also the Nordic name Lillemor meaning “little mother”.
A nickname possibility would be [name_f]Lily[/name_f] which ties in with the meaning of [name_f]Sue[/name_f].
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[name_f]Anya[/name_f] means mother in Hungarian.