If I traveled to China tomorrow, I'd buy bike parts, including an ultegra di2 group from a Chinese website. The inflation on AliExpress in the last four months is absolutely insane, so if you can buy in China directly, you can save a huge chunk of the total build cost.
I wouldn't buy a magene groupset, having installed several ltwoo groups. If they don't want to distribute in the west, there's certainly a reason for it, and a bike that doesn't shift is no fun, I can tell you that...