There are some pretty good ones in QoD. "Ra's Evil Grin" and "Sewers of the Underguild" are excellent and gauged for 11th and 15th level respectively. "Emeralds of Highfang" is recommended for "high level" - I'd estimate 16th-18th level. Bear in mind that modules from Frog God Games are usually more dangerous than those published by WotC, so bumping any of these up another level or two wouldn't be excessive.There's some in Quests of Doom, no idea if they are any good.
There are some pretty good ones in QoD. "Ra's Evil Grin" and "Sewers of the Underguild" are excellent and gauged for 11th and 15th level respectively. "Emeralds of Highfang" is recommended for "high level" - I'd estimate 16th-18th level. Bear in mind that modules from Frog God Games are usually more dangerous than those published by WotC, so bumping any of these up another level or two wouldn't be excessive.
It's just that: the foundation isn't good. High level 5E material is written like low level 5E material: for neophytes.You can scavenge the end (high level) parts from any of the published modules and modify them for your party. But the primary thing to remember at those levels is that you should expect to always customize to your party. The mix of powers and magic makes it impossible to write a universally appropriate module for those levels. All the authors can do is give you a good foundation.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.