If I recall correctly, they purchased Mi-26s from Russia. Which means we'll see a Chinese domestic variant in 10 years
There is in fact a collaboration between the Russians and Chinese into developing a Mi-26 successor helo.
The Russians are developing an engine for this helicopter initiative (PD-12V).
China also supposedly has a collaboration with Ukraine to manufacture the An-225 in China. But given US interventionism in Ukraine I don't know how far that project went through. I also think the An-225 is a bit too large for comfort and expensive. The Russians supposedly have a project with similar payload capability called Slon (Elephant) which would use the PD-35 engine which should be available near the end of this decade. So it would be a 4x engine aircraft with similar payload as the 6x engine An-225.
With regards to the A-400M replacement I think the Chinese could easily come up with one. Well a C-130 replacement at least. They could do like Embraer did with the KC-390. Or pickup an Antonov design with either the An-178 or An-188 projects.
