Hmm…I love the way Lark Adelaide sounds the best but I think you really want Lark Rosalie by the way you wrote about it so I’d go with that one.
Other possibilities/mixtures ( a lot of these are old school bird names/terms):
Branwen Rosalie
Merle Rosalie or Merle Adelaide (I adore this one for you!)
Avelot Rosalie
Arnelle Rosalie
Morrigan Rosalie
Raven Valentine / Valentine Raven
Or mix and match with other middles as you fancy. Do you like double barrels or maybe not because your other girls don’t have them?
Briallen Lark Amara
Lark Rosalie Faye
Beryl Ivy Robin
Robin Verity Elise
Merle Verity Rae
Avis Rosella Willow
Poe Verity Rose (this one’s very roundabout–from the poem “the Raven” by Poe)
Poe Verity Merle
Poe Adelaide Rose
Hopefully these help! 