They are names related to each other and both means hard work.
I like [name_f]Millicent[/name_f] because it’s :
Familiar, but unusual and accessible from nickname [name_f]Millie[/name_f]
Sweet and soft sounding
Dislike grandma association
I like [name_f]Melisande[/name_f] because :
Historic, literary and [name_m]French[/name_m] royal association
It’s soft, grand yet graceful sound/image
Dislike the fact it may be too unusual for non-English, non-[name_m]French[/name_m] speaking country.
I also decided against the accent over e letter in name.
Combos :
[name_f]Freya[/name_f] [name_f]Millicent[/name_f] and [name_f]Melisande[/name_f] [name_f]Carys[/name_f] - both first and middle are used here.
I love [name_f]Melisande[/name_f]. There are so many nicknames you can play around with.
[name_f]Melisande[/name_f] [name_f]Carys[/name_f] is gorgeous.
[name_f]Freya[/name_f] [name_f]Melisande[/name_f] works as well.
Both names are lovely! I slightly prefer [name_f]Millicent[/name_f], I like how sweet it is and I don’t think it sounds like a grandma name. Out of the two combos I prefer [name_f]Melisande[/name_f] [name_f]Carys[/name_f], though if [name_f]Freya[/name_f] [name_f]Millicent[/name_f] was [name_f]Millicent[/name_f] [name_f]Freya[/name_f] I’d [name_u]LOVE[/name_u] that. Personally I’d like a three-syllable middle name with [name_f]Melisande[/name_f].
I prefer [name_f]Melisande[/name_f] to [name_f]Millicent[/name_f], but I think you’ve raised good points about [name_f]Millicent[/name_f] being more accessible in your circumstances, and I adore first name [name_f]Freya[/name_f].