I'm not a fan. I find it cutesy and twee and little girlish.
Polly? Go ahead.
Anna? If you really must.
Polly with the middle name
Anna... cheesy, but easily overlooked... but the actual name? No. I have a bit of a block on it, to be honest. I think it can be forgiven as a middle name in that you can use it but the poor girl doesn't have to go through life broadcasting it as (part of) her name unless she really loves it.
I like:
Beatrice Pollyanna - because I'm a sucker for
Beatrice.
Iris PollyannaLucile PollyannaMathilde PollyannaRose PollyannaSusan PollyannaVivien Pollyanna