I have stayed at both. I'm SUPER finicky about transportation to & from parks (times & options). I like that WL has boat & bus options. I like that POFQ has a one bus stop option with boat option to DS. WL will likely share buses with other resorts. POFQ will sometimes share with POR, but should be first to pick up & drop off.
WL has interior door, one building layout. Where POFQ has an exterior door, multiple building layout.
Both have really spectacular theming & look to the resort. Our stay at POFQ was one day after a stay in New Orleans & visit to the French Quarter. My DD said 'they nailed it', albeit a little cleaner.
POFQ sells beignets & foods like gumbo or shrimp po'boys. (The beignets are a very distant second to the real deal in NOLA). If the 5yo is very into Princess & the Frog, might be a consideration.
I have to give a slight edge to WL pool.
I have to give an edge to WL for lounge/bar areas.
POFQ has quick access to DS for dining. WL has quick boat access to CR and then any monorail resort from there (important if you're picking these locations anyway for ADR or if you want some character meals they offer).
Both have sister properties worth mentioning. WL is next door to FW and offers TONS of fun things like Chip'n'Dale campfire, archery, bike rentals, canoeing, pony rides, carriage rides, fishing, & marina rentals. They have a great comfort food buffet. You can access FW by boat, there was a direct bus (double check if this still operates), or a 1 mile wooded walking path. POFQ is next door to POR and offers a great dining option at Boatwright's, carriage rides, a great bar, & beautiful grounds. This can be accessed by checking with a bus driver that they are stopping there next, by boat, via the DS boat, or by beautiful riverside walkway.
WL has its own character meal now.
WL has a nightly light parade on the lagoon.
Our favorite trip to WDW ever was with a stay at WL. I still question if it was WL or just the people & experiences we shared that made it so great. I also know that the last several checks of WL is pricing me out of staying again. Every time I compare to the price of POFQ, I say ' well that would free up $100 (or more) for food everyday of our trip.'