No, I'm not. Chromium doesn't exist in Windows unless you install a program that includes it. Chromium web engine is "native" to the chromium web browser, not to any OS (except maybe ChromeOS). As espi mentioned, Internet explorer's mshtml is the only engine "native" to Windows. Just look at the Opera browser, they changed web engines from Presto to chromium; that's not using "what's native to the platform" (Opera works across all OS's with chromium, except for iOS for the restriction I mentioned before), it's using what the developers/company want to use to render their pages. Nothing in Windows itself provides any of the chromium engine "pieces"
Chrome has EMET disabled because it's own memory protections conflict and it just won't execute.
When you're make a web view for Windows you're either bringing a long your own rendering or using Edge because it's included.
No one wants to secure their own rendering which is why they all use whatever is already there which is EMET which is a pita to test so they just go with Edge.
native is just jargon for "what is already there."
EMET? The framework that was end-of-lifed in 2018? I'd bloody well hope Chrome doesn't use something that isn't supported anymore.
Chrome's sandboxing is weird and prone to breaking, but at least it isn't stuck relying entirely on a kernel framework exclusive to an OS that people are extremely hesitant to keep up-to-date.