Somehow, I missed that Ecowitt is a retail sales subsidiary of Fine Offset, and now I understand all of the mismatch between what Ecowitt and Ambient Weather (and other retailers?) offer. Good grief, you fine folks are very dedicated to be able to keep up with this stuff. I'm sure the two companies didn't appreciate me asking questions about interoperability, but oh well.
I followed no one's advice, and bought a WS-3000-5 (AW), added three sensors (including two of the new WH31P sensors, working great so far), and the ObserverIP. I got exactly what the Ambient Weather website said would work together. You can put all of that in the cart with a few clicks from the same page. Well, it does, but HUGE CAVIOT. There is no way of knowing from their website, or the manual online, or anywhere that I could find that the ObserverIP apparently will not report an Outside temperature without an array connected. Unless, you are using it configured as a WS-0800, which will only use WH32 (B and E) sensors, and according to the AW support guy, will then not accept any additional sensors (channels 1-8). The WS-3000 of course will not accept WH32 sensors, so now I've gotten close to my planned usage, but still further away than I was expecting. I gave up on a battery operated display.
Yes, I can see all of the sensors on the AW.net dashboard, but now I can't set IFTTT triggers (EDIT: Ok, I found a way to use values for other sensors). I went with the ObserverIP because I wanted the device not on wifi, and I can vlan (and have) it easily. And, I have some other things that was going to do with the shared data (without sharing the entire dashboard).
Now that I know the backstory, it makes sense. I still don't understand why they can't have the option to assign one of the eight "additional" sensors as the "Outdoor" sensor, but I'm sure there is some amazingly business minded reason for it.
Sorry for the short rant. I come from an industry (a/v) where interoperability is paramount for a device manufacturer to succeed. Not just between brands, with a standard communication protocol, which this weather equipment clearly works on that principal. But also within a product line. This ObserverIP should be able to see and use anything AW sells (EDIT: of the Fine Offset manufacturing), and mix and match. It makes me wonder how much of the software engineering AW had control over. Possibly not more than putting the name at the top of the web based GUI.
Anyway, if anyone has a suggestion for me, I'll take it, but I guess I'm going to do exactly what was going to bug me from the beginning: have two sensors outside to accomplish the same task. Adding a WH32E to the cart... Edit: Well, maybe I can find more work around for this.