I know fans had issues with Jin x Christie in the live-action Tekken movie because several fans ship Jin x Xiaoyu (they had more interactions in canon whereas Jin didn't really interact with Christie in the games), and that's perfectly fine.
However, I do think these two can work in an AU.
Jin lost his mother, and Christie lost her grandfather, so there can be a bit of a bond between the two over their losses. Plus, Christie could genuinely ease Jin's pain with how optimistic she can be.
It's also worth noting there were a few pieces of fan art and fanfiction pairing Jin and Christie together some time before the movie was even in pre-production.
Plus, Christie and Xiaoyu aren't the only ones Jin has been paired with. There was also a Tekken 3 manhua that paired him with Julia, and that pairing had quite some shippers too.