There are shade tolerant water lilies, but they still need 3 to 4 hours of sun to bloom. They will do better with more sun. You don't say what size your pond is, but I am grouping the following by size.

Dwarf/Pygmy - common minimum depth of water over plant crown is 12 inches

• Graziella - pink, spreading 12 to 30 inches
• Helvola - pale yellow, spreading 8 to 24 inches

Medium - common minimum depth of water over plant crown is 18 inches

• Arc-en-ciel - blush pink, spreading 36 to 48 inches
• James Brydon - red, spreading 30 to 48 inches

Do a search for shade tolerant water lilies to find lots more that I did not list above because I don't know how large they grow.

I know tropical waterlily, King of Siam is pretty shade tolerant. Miami Rose is also reportedly shade tolerant but I just got that one so havent experimented with it

I had KoS by a mulberry tree that shaded it late afternoon and it still flowered.