I love both [name]Matilda[/name] combos, but would choose [name]Willow[/name] myself.
I don’t like [name]Camellia[/name], but [name]Sophie[/name] is the better match here, stylistically and for flow. Same for [name]Veda[/name] [name]Caroline[/name].
[name]Helena[/name] [name]Phoebe[/name] is precious and works way better than [name]Molly[/name] for me.
I don’t like either name you have paired with [name]Fiona[/name], but I suppose [name]Ellie[/name] is marginally better than [name]Marley[/name].
I like [name]Matilda[/name] [name]Willow[/name] and [name]Fiona[/name] [name]Ellie[/name] on your list, but I think [name]Fiona[/name] [name]Willow[/name] would go wonderfully together.