Deorwynn

Derwin and Darwin could be considered as modern English form of Deorwynn (Source: https://anglisc.miraheze.org/wiki/Anglish_Given_Names).

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Derwin could be Latinized to become "Derwina" or "Derwinna". Based on endings of other Old English feminine names ending in -wynn (like -wyn, -wynne, -wyna, -wen, -wena and -wenna), I imagine that Derwynn, Derwyn, Derwynne, Derwyna, Derwen, Derwena and Derwenna could work as other forms.

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Darwin could be Latinized to become "Darwina" or "Darwinna". Based on endings of other Old English feminine names ending in -wynn (like -wyn, -wynne, -wyna, -wen, -wena and -wenna), I imagine that Darwynn, Darwyn, Darwynne, Darwyna, Darwen, Darwena and Darwenna could work as other forms.

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Unfortunately I can't find sources showing these though.

I'm wondering if Derewina may be another form? I found Derewina here: https://archive.org/stream/domesdayofstpaul69stpa/domesdayofstpaul69stpa_djvu.txt