I don´t really see why you should buy a 13400 cpu and use 16gb ram only? Ram is cheap, fill it up! 😁
If you dont have the money, step down the cpu a bit and throw in more memory.
Kodi wants 4-8gb to work properly, home-ass at least 2gb, 4gb is good and 8 is better depending on how many units connected and the automation beeing done with it. Pfsense, at least 2gb.
Yeah, kodi can roll on 2gb, pfsense works at 1gb, home-ass can work with 512-1gb - but it wont work good. If Kodi runs a cronjob indexing your movies and due to that home-ass takes 8 seconds to reply and Blue Iris has a 4 second gap in recordings (I'm exaggerating of course, but not far away) 😁
You are peaking the 16gb limit already with the VM´s alone, add Blue Iris to that and its over.
Type or brand of the motherboard, brand of the storage and so on doesnt matter much if they dont provide any function or support you absolutely need.
You need computing power, speedy drive(s) and ram. Thats it.
If you are stuck with any of these, add ram. Step down the cpu if needed, just add more ram.
I would go with at least a mirrored setup on the NVME´s, if you dont need the space go with 2x500. Depends on how important the stuff you are going to store on it is.
Hardware on both machines looks good in my opinion for what you need it for, ram and single drives is the only thing i have opinion about.
It´s possible to argue that one of the motherboards are better than the other, or the PSU is better on one but it won´t matter for what you are going to use it for, at all.
Cooling, type of NVME, color of the motherboard and so on is on you, take what you think looks good and the preferences you have on noise from the machine. Performance wise its not much difference between the 2 in your listing.
I havent started a game on my computer since 2001 so the gaming-part of the machine is not my cup of tea.
