Seeds are largely prohibited from transporting into China. Or out of China. Or other countries.

One can take seeds into the PR China but must apply for permission before one's trip.

I would expect that approval would be slow, and one would want to apply far in advance, but I have never tried. Also beware that some classes of plants are protected by CITES regulations that would require additional permits.

As for plants that might work:

Clivia

many cacti and succulents

many palms

Streptocarpus and other Gesneriads

Look for seeds or starter plants of what seems like it might have suitable characteristics after you get over there. Instead of trying to transport plant material into China.

Many/most seeds can survive for years without you having to do anything special. The problem is not with having seeds survive a trip, it's the import regulations (as others have noted).