I like lightweight chairs that can be moved around.

Upholstered chairs with a high enough back to lean your head back. Ottomans for sure.

And speaking as an older person, please no low chairs.

I agree with sushi, and also back support. Can't stand chairs with a hole just where I need lumbar support. As an older person, I would rather sit in the shade; older skin is thin and delicate.

Yes, those lineups of chaise- style loungers look like a hotel and not like comfortable for gathering, and not sensible to spend hours in the sun, so depending on who uses pool, maybe only couple of them for brief drying off and warming up..

area seems important

As noted above, you basically want a chair (s) that are normal height, normal contour, with some removable cushions. I don’t think you need massive cushions that take up a lot of storage space, but may want to shop some better brands than discount store types, for the right ones. Again, I’d plan different furniture features for a covered patio that for “sitting in the sun” . I’d even plan un cushioned, dare I say plastic, chairs for brief drying out spells - why soak a cushion for that. This is if anybody actually swims.
And a couple of movable ottomans is great.

Thank you for all the confirmation everyone! I appreciate it!

Also include a nice ottoman for the chair.