I go through phases with these. I like
Elizabeth in general, and this is a pleasant enough form. I'm not always keen on the 'belle' ending in names, but it's okay here, and '
Isa' is nice. don't pronounce them differently.
Isabel feels more Spanish,
Isabelle more French. Both are very feminine -
Isabelle slightly more so, it has a princess-y vibe whereas
Isabel is slightly more clipped. If I were to use the name, I would probably use
Ysabel (as a middle name because the spelling is confusing). I wouldn't use any variant atm though because it's so popular, and soon it'll be awfully dated.
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"That cynicism you refer to I acquired the day I discovered I was different from little boys."