It is your responsibility to provide the evidence for your claim.
Which has been provided. Obviously because it shows something you don't like you are blundering around first trying to say "Aha, but the effect is far too small to get those results" and then, embarrassingly, you realised your mistake so hastily amended that. hoping we wouldn't notice, to say he was "trying" to get certain results which makes zero sense. He just took some readings and showed the results.
I'm sorry you don't like the results, but they are what they are.
I did not claim that this effect existed for scales. You did.
That sentence alone is another betrayal of your ignorance of things. The effect doesn't exist "for scales", it simply exists.
The hypotheses are simply this.
Firstly, if we are living on a spinning ball then a centrifugal force should be acting. The magnitude of that force should vary depending on your latitude. And if you do the maths you'll note that we shouldn't all go "flying off" like some of the sillier FE people claim, but there should be a measurable difference at different latitudes. And oh look, the same dude did another video which demonstrates just that:
And note that at the end of the video he urges people to do their own tests and not just take his word for it. So go on then, what's stopping you?
Secondly, if you're travelling going East then you are going with the rotation of the earth which would make the magnitude of that centrifugal force higher, if you're going West you're going against the rotation of the earth so the magnitude will be less.
Which is what the original video shows. You don't have to be on a plane but they go fast enough to mean the effect is easily measurable with the right equipment.
So yeah. We have two hypotheses, the two experiments test those hypothesis. The results don't prove the hypothesis, that's not how science works. But they are in line with what you'd expect if the hypothesis is true.
The effect was originally discovered by ships that were measuring the gravitational field of the earth. Which is a force.
Scales measure weight, which is also a force - it's actually the force acting on a body
because of the gravitational field of the earth. So I'd absolutely expect an accurate scale to be able to detect this effect. I'm sorry if you don't understand that but I don't know what I can do about that.
I wouldn't expect there to be a huge body of scientific evidence on this because it's based on the premises that
1) The earth is a spinning ball
2) Centrifugal force is a thing.
Neither of these things are controversial. Repeat experiments were done - also with ships, I don't know if you'd get accurate readings on a scale on ships which rock and move far more than airplanes do, and ships are quite slow so the effect would be harder to measure. But given that the results are in line with a globe earth model which is known to be true, I don't think you're going to get a research grant to pursue the matter. It's an accepted effect, the reasons for it are understood.
What is the FE explanation?
If RE could actually show its claims, they would have done that long ago
Well, they have. All you're doing is either calling it fake, misunderstanding it or hand waving it away for various spurious reasons.
It's very easy to "prove" yourself right if you ignore or call fake all the evidence showing you to be wrong.
Luckily, these effects are relatively easy to test and as I said the guy actively encourages you to.
There's a bit of outlay but I'm sure the FE community could raise enough money for an accurate scale and a reference weight.
Then you can test this for yourself. I look forward to the results.