Hey there,
it seems UE4 has issues with Ryzen OC and/or the latest microcode updates for that platform.
In my case, PUBG(1) and AotS(2), CPU OC seems to be the problem, particularly with the latest microcode updates for Ryzen+.
(1) https://forums.playbattlegrounds.com/topic/212986-crash-issues-information-collection/?page=3&tab=comments#comment-802681
(1) https://forums.playbattlegrounds.com/topic/205712-pubg-is-not-friendly-for-overclocked-pcs/?page=2&tab=comments#comment-731349
(2) I know that AotS isn’t UE4, just mentioning it since this was clearly OC related with that game too (OC on = very frequent crashes, OC off = fine).
Which from my POV is a hint that you might need to check this with board manufacturers. In my case that would be Asrock (X370 Taichi 4.60 BIOS [there is a 4.70 from 04-26, I will test that later today. Doesn’t sound important, but the changelog before wasn’t OC-related too, so…(“Enhance compatibility for Raven CPU with Intel WiFi.”)]).
(1) Since they also mention HPET: I will not test all the HPET settings again after already having to remove my OC, this is for you to test.
With OC, disabling HPET didn’t change much -> https://forums.playbattlegrounds.com/topic/212986-crash-issues-information-collection/?page=3&tab=comments#comment-794778
“Man, your OC simply sucks”
Yup, that’s why I and countless other people can run that exact OC for ages in games/hardcore stress tests without the slightest problem.
Sounds legit.
^ Which of course again speaks against a particular OC/microcode problem…yeah so we might have a little bit of fun until we can tackle the original issue behind this…
Or you simply send an intern to Bluehole since they definitely cannot code properly and might be to blame for this and 98% of the other bugs in this game, and he fixes everything even though he has only been working for you for a week or so.
But for the slight chance this isn’t their code, but some kinky bug with UE4/OC/microcode, let’s see what we can find out via this post 
Best regards
PS: No I would not like to post this via a 1:1 support ticket.
This is too big of a problem to be placed on the side since it affects this well known AAA BR flagship