It would certainly appear to lack the FCC ID label/marking it is required to have if it is FCC certified. So probably not. Thus, it also appears doubtful whether it can legally be marketed or sold in the U.S.
IANAL, But I think device as-is can likely be sold and marketed perfectly fine. Test-kit and dev-kit stuff is regulated a bit differently under the assumption that it's not going to be in mass use, and also that it's likely going to be used to develop another product that will get the fcc certification.
The link you provided appears to say the opposite about kits:
"Based on the definition above, it looks clear that non-authorized kits that are intended to form a complete product when fully constructed are technically not legally permitted to be sold in the US. That is because if you are marketing and selling a kit to an end user, which the user will then build into a full product, there is no reason to suspect that the normal rules would not apply."
The subassembly rules could work, if they apply, but I don't see how this product fits the definition of a sub-assembly:
"No authorization is required for a peripheral device or a subassembly that is sold to an equipment manufacturer for further fabrication."
In fact, I think it's a stretch to say that any of these test-kit, dev equipment, or subassembly rules apply. This basically strikes me as being marketed as a consumer product -- albeit a product for very tech savvy consumers.
A search for "Malouf" on the FCC registration website provided no matches. Most likely this product is not registered.
In addition, this product lacks a CE mark and has no UL/FM/CSA listing. I'm curious what creepage/clearance requirements were factor into the design. This product is potentially dangerous if the relay is switching line voltage.
This is the exact reason why I didn't see through my plan to build and sell the EspUSB (a very small ESP board that fits inside a USB-A port).
I got 3 units built for myself by PCBWay at a cost of $77. I got quotes of ~$500 for 100 units from Elecrow and Makerfabs, but didn't know what to do with the other 90.
Although I really want this great little gadget to be easily available, I can't afford $10,000 for FCC certification, and therefore I have no solution.
If anybody wants more details, email espusb@gmail.com and we can chat about it on there.
There are various exemptions for subassemblies and other non-end-user products. Those may not always apply. However, in practice, a product that's sold in small quantities and does not in fact emit egregious electromagnetic interference is unlikely to attract enforcement attention. So a fair bit of skirting of the rules does go on.
Based on the PAL project and WiFi capability, I think the ESP8266 does emit electromagnetic radiation. Whether it's interference or a feature depends on your perspective.
It would certainly appear to lack the FCC ID label/marking it is required to have if it is FCC certified. So probably not. Thus, it also appears doubtful whether it can legally be marketed or sold in the U.S.