That's the very loud generator I used to try it. 500w continuous on that one is a fantasy spec. I had to run 250w (5 amps 48v) chargers one at a time on it. It was a bit much for me to carry on my bob trailer, at 30 pounds it made the bike handle funny. But a more stable trailer like the one I made out of bmx wheels and an aluminum ladder would carry a heavier harbor freight 2000w generator similar to the one in the video. https://www.harborfreight.com/2000-watt-super-quiet-inverter-generator-62523.html For that trailer, I had a custom hitch welded to the back of a cargo bike I built specifically for towing. So no funky kid trailer hitch, I had a rock solid rear bumper on the bike to hitch to.
This one also has a fantasy wattage spec, it struggles to go more than 1000w continuous. I have one to run my RV, but it cannot pull the air conditioner, which takes about 1300w to keep it going. But the bigger generator is WAAAAY quieter, and will pull a 1000w charger. Or two 350w satiators at once.
But I found the best solution was still a crapton of batteries. When I built that towing bike, I made it able to easily carry 48v 80 amp hours, a whopping 4kwh of battery. In practice, what I did was this. I'd carry about 30-40 amp hours of decent newer battery, plus another 30 or so amp hours of old puffed up tired lipos 3-4 years old. If I pulled light on that second old battery, riding less than 20 mph, I'd wring 20 ah from those. This gave me 80 mile range at least. I needed that, since the distance between western towns in the desert is about 60-70 miles, because trains in 1880 needed water every 70 miles or so.
Anyway, all that battery weighed less than the generator, and I did not have to listen to that loud piece of shit run for 6 hours of riding. Plugs were hard to find!, but once I knew of a few, I could ride to nearby towns 70 miles away and know where to plug in. Then a long wait to charge there, sometimes at a city park, or even buying a charge at a campground with electric hook ups.
A typical free range 15 amps gfci plug will pull a 1000w charger. But not if its also got two coke machines and an Ice freezer running on it already. Best to have another, smaller wattage charger on that trip just in case.