Hello! For 6 years I’ve been using an Intel i5-4690k for my main rig (yes yes I should have updated a long time ago but I have been saving up money). Since we are not so far away from the release of UE5 and have things like black Friday and Christmas coming up I was considering on getting a new rig as many parts need upgrades. Since I write some C++ in my game development I am faced with longer compile times because of my older CPU. One time I was fixing a small bug in a piece of C++ code and each recompile took 7-10 minutes which was very frustrating. Currently I am debating between AMD Ryzen 5 5600X and Intel i5-10400F. I would like to ask if anyone had used these processors and how is their performance in Unreal Engine C++ development? I am also open to some other suggestions for CPUs. Thank You in advance! 
My vote is currently for AMD.
Cores help compiling (and packaging) quite a bit. If you can, go even more cores, like 5900x. It has double the cores and is faster.
The other huge game changer - get an m.2 SSD (if you dont already have one). This is probably an even bigger boost for compiling.
(Make sure both engine and project are on the SSD and not on a regular HD).
BTW - The new AMD boards (like x570) support PCIE Gen 4, which makes m.2 SSD even faster.