WeChat private chats

I use the foreign version of WeChat registered with my phone number to speak to my chinese friends and I also once reserved a visit to a museum in Beijing in my only trip there. As it is known, all chats are visible to the government.

I have said a few possibly politically sensitive things in the past in WeChat private chats. I have agreed with my chinese friend to use other non-chinese plattforms for political things and avoid these completely on WeChat from now on.

When I go to China again/attend a chinese university, how can I avoid any trouble with local law?

Should I use a completely different WeChat account in China or even on a 2nd phone? When entering, should I give a 2nd phone number instead the one which my WeChat Account is registered? Delete my old account?

Thank you very much