[name]Charlotte[/name] is one of my all time favorite names, and I think that if you choose a name with a similar classic and feminine feel, it would a gorgeous combination.
Favorites I’ve read so far:
[name]Iris[/name] [name]Margaret[/name] (I think it’s a fun bonus that [name]Iris[/name] looks like “Irish”)
[name]Clara[/name] [name]Margaret[/name] ([name]Clara[/name] also looks like [name]Ciara[/name], which seems [name]Iris[/name] according to the Internet)
[name]Adelaide[/name] [name]Elizabeth[/name] or [name]Adelaide[/name] [name]Margaret[/name] (beautiful!)
[name]Primrose[/name] [name]Margaret[/name] (what a fun, beautiful way to get to [name]Rosie[/name])
Other first name ideas:
[name]Fiona[/name] (I just love a sibset of [name]Charlotte[/name] and [name]Fiona[/name]!)
[name]Sabrina[/name] (Celtic name that brings both magic and [name]Audrey[/name] Hepburn to mind)
[name]Violet[/name] or [name]Viola[/name] (if you like [name]Rose[/name]…)
[name]Guinevere[/name] or [name]Gwenyth[/name] or [name]Gwendolen[/name] (Welsh, so I’m taking some liberties here)
[name]Cordelia[/name] (also Celtic! And just think of the NNs: [name]Cora[/name], [name]Cory[/name], [name]Cordy[/name], [name]Dell[/name], [name]Delia[/name], [name]Kelly[/name], [name]Rory[/name], [name]Lia[/name], [name]Elia[/name], [name]Celia[/name], etc)
Variations on the names you posted initally (for which [name]Rosie[/name] and [name]Calla[/name] would be excellent nicknames):
[name]Rosemary[/name]
[name]Rosanna[/name] (I think this spelling takes the [name]Roseanne[/name] out of the equation completely)
[name]Rosalie[/name]
[name]Rosette[/name] or [name]Rosetta[/name]
[name]Callista[/name]
[name]Calypso[/name]
And what if you considered [name]Elizabeth[/name] or [name]Margaret[/name] variations as a first name? I totally understand that it isn’t part of your naming pattern, but you could use an [name]Elizabeth[/name] variation with [name]Margaret[/name] as a middle or vice versa. The following names either derives from these two names or have similar letter combinations and I put my favorites in bold.
[name]Elizabeth[/name]:
[name]Elspeth[/name] (Scottish actually)
[name]Elsbeth[/name] (same)
[name]Eliza[/name]
[name]Eliana[/name] or [name]Elianna[/name]
[name]Elsie[/name]
[name]Eloise[/name]
[name]Eleanor[/name]/[name]Eleanora[/name]
[name]Elodie[/name]
[name]Elisheva[/name]
[name]Lisbeth[/name]
[name]Lisabeth[/name]
[name]Lilibeth[/name]
[name]Betsy[/name] (a lot of full names can also get you to this nn. My fav: [name]Beatrice[/name])
[name]Betty[/name] (same!)
Bethanna
Annabeth
[name]Annalise[/name]
and anything that ends in [name]Bel[/name], [name]Belle[/name], or [name]Bella[/name] ([name]Amabel[/name]/elle/ella, [name]Isabel[/name]/elle/ella, [name]Anabel[/name]/elle/ella, [name]Clarabel[/name]/elle/ella, etc)
[name]Margaret[/name]:
[name]Greta[/name] (my favorite variation)
[name]Gretchen[/name]
[name]Gretel[/name]
[name]Greer[/name] (not a fan personally, but it feels related)
[name]Marguerite[/name]
[name]Margot[/name] or [name]Margo[/name] (ok my other favorite)
[name]Pearl[/name] (the Greek meaning of [name]Margaret[/name])
[name]Daisy[/name] ([name]Marguerite[/name] is “daisy” in French)
[name]Maisie[/name]
[name]May[/name]/[name]Mae[/name]
[name]Mary[/name]
[name]Mabel[/name]
[name]Mara[/name] or [name]Mira[/name]
[name]Magnolia[/name] (love! and can lend itself to [name]Margaret[/name] nn [name]Maggie[/name])
[name]Mirabelle[/name] (kind of a smoosh of [name]Elizabeth[/name] and [name]Margaret[/name] diminutives)
[name]Marybeth[/name] (same)
[name]Maryanne[/name]
[name]Marissa[/name]
[name]Marigold[/name]
[name]Marina[/name] or [name]Marnina[/name]
[name]Marmaduke[/name] (hah! [name]Just[/name] kidding)
[name]Michelle[/name] (adorable with [name]Charlotte[/name])