Check out the link above to see a custom build list.
-- What I chose and why --
CPU: 9700K will give you best core clock frequencies (amount of tasks per core) which photoshop prefers over multi-threaded perforamnce. So AMD performs worse on photoshop.
RAM: Anyhting above 3200MHz is ideal for optimal perfomance. Trident Z being the best ram on the market right now. And you have the money to spare apparently for the best.
Monitor: You can choose any other monitor you prefer but I highly recommend a monitor that has these qualities:
IPS PANEL (For best colors)
Anything above or around 400Nits (this is max brightness, anything above 400 gives you HDR support, meaning true blacks and whites) though this isn't critical, 300 will also work fine.
Above 60Hz refresh rate (The smoother you move around around your screen the better it feels to edit, this is subjective though)
27" screen size. The more real estate the easier it is to edit larger files. This comes from personal experience.
GPU: The 5700XT is a cheap but powerful card that will handle 1440p gaming if you so choose to play games. You don't need a super powerful graphics card though to photo edit. Even an old video card will be fine, just as long as it has the proper video output ports for your monitor.