Thru Xi'an

I've tried searching multiple ways but just want to confirm my understanding so I have time to get a Visa if needed (forgive my comprehension skills haha).

I will be flying LAX-Bejing with a 5 hour layover in Xi'an. I plan to stay in Bejing for approximately 48-72 hours, then flying out to Thailand.

Approximately 3 weeks later, I will be flying from Tokyo-LAX with a layover again in Xi'an.

I initally thought I would be exempt, but some posts mentioning multiple domestic stops indicate a Visa will be required. Is that accurate?

Thanks so much.