There is no way to tell for sure (unless I had a time machine. That would be great :).), but I’ll have a crack at it:
[name_f]Flora[/name_f]- No. Unless you are in the UK, then it may follow [name_f]Florence[/name_f].
[name_f]Sylvie[/name_f]- It will rise, but I don’t think it will be mega popular.
[name_f]Luna[/name_f]- Yes. Definitely, as a sort of [name_f]Lucy[/name_f] / [name_f]Lana[/name_f] hybrid.
[name_f]Marigold[/name_f]- No. I don’t it will rise much.
[name_f]Magnolia[/name_f]- No. It might rise, but I don’t think it will become mainstream.
[name_f]Olive[/name_f]- Yes. [name_f]Isla[/name_f] [name_m]Fisher[/name_m] and [name_u]Drew[/name_u] Barrymore both have [name_f]Olive[/name_f]'s, and this name is definitely on the rise, as an alternative to [name_f]Olivia[/name_f], [name_f]Lily[/name_f] and [name_f]Daisy[/name_f].
[name_u]Echo[/name_u]- No. Definitely not. [name_u]Echo[/name_u] was reduced to just an [name_u]Echo[/name_u], and the whole idea is a bit too odd for most baby namers (I do like it though).
[name_f]Clover[/name_f]- Maybe, following [name_u]Juniper[/name_u], but not until after [name_u]Juniper[/name_u] peaks.
[name_u]Juniper[/name_u]- Yes. It has the elements of [name_f]Juliet[/name_f] / [name_f]Julia[/name_f] rolled into a cute and sprightly nature name. I think this name will rise a lot.
[name_f]Mabel[/name_f]- Yes. I don’t think it will become mega popular, but I think it will become more popular.
[name_f]Lucinda[/name_f]- No. Too buttoned up for mainstream parents.
[name_u]Hero[/name_u]- No. To ‘out there’ for mainstream taste.
[name_f]Lillian[/name_f]- Yes, I think so. I know a few [name_f]Lillian[/name_f]'s, and it is a good quiet classic: I think it will rise.
[name_f]Lucia[/name_f]- I know 2 [name_f]Lucia[/name_f]'s. I think it will become more popular, maybe breaking into the Top 100, as an alternative to [name_f]Lucy[/name_f], but I don’t think it will be the next [name_f]Emily[/name_f].
[name_f]Martha[/name_f]- In the UK, yes. In Australia and the US, I can’t see it happening.
[name_f]Lilac[/name_f]- Maybe, but probably another 10 years, as an alternative to [name_f]Lila[/name_f] and [name_f]Lily[/name_f].
[name_f]Opal[/name_f]- If [name_f]Pearl[/name_f] becomes popular, then yes. If [name_f]Pearl[/name_f] doesn’t, then I don’t think [name_f]Opal[/name_f] will become mainstream.