I have never seen any of these consoles.
https://twitter.com/hallyvorc/status/1185607428613656576 -> They seem to be empty molds (no connectors, no PCBs). Likely test designs that never made it to the market or just fancy design by an individual as you suggested.
The second one seems fairly unrealistic. Probably just an artistic design. As you can see it seems to be designed as a portable console like the IQ-901. But it's not really hand-compatible at all. Also such cartridge insertion system wouldn't work at all due to the very different size of Famiclone cartridges. For example, "TV Game Cartridge" large shells don't even fit in the NES due to their thickness with a classic 72-60 pins adapter. I think the second one is rather an Atari 2600 clone (due to the cartridge shape).
Also on the second one, it seems there's no mechanism to actually close the cartridge insertion part. For me it feels just like a mockup and it was never intended to be marketed or sold.
https://drive.google.com/file/d/1Jxa0EBqc67BqzcNjCHnD_Y-9Y-lIp_tJ/view?usp=sharing -> Shape is a mix of Atari 2600 clones, Space Shuttle (MSX) clone and Bit Creator 70. I would say it was likely released. Maybe it was not seen yet because it was not sighted. Supertone was an established business that manufactured PC Motherboards among other things.
https://twitter.com/hallyvorc/status/1185458858090647553 > Doesn't remind me of anything.
佳寶電子工業 (1990) > never seen, probably it never went past the registered trademark as it seems to be portable with a screen, way too expensive and idealistic for a 1990 product.
As to clones, the first ones are from 1987 definitely. Some IQ-201 have chips from week 4x of 1987. There's advertisements from August 1987 of IQ-201 and IQ-180 (never seen any) that are known to exists. So it's not unrealistic they all planned their Famiclone by mid-late 1987.
But EFA Corp clone is definitely not made for Famicom, cartridge shape doesn't match.