Two very similar species with blue tinted white flowers on tall stems. The main difference seems to be that leveilei (on the left, below) is an altogether more substantial plant

Anemone leveilei

Purple blue tinted white flowers with dark anthers are produced on long arching pedicels in an umbel on a stout leafy plant up to 2ft tall. For moist alpine or woodsy conditions.

White flowers tinted steely blue on the reverse and with similar coloured anthers on slender wiry branching stems. This species is adaptable but is particularly useful in wet sites.
2L pots ~ £7