Depending on states, change guilty plea before...

Too late. In some states you cannot change not guilty plea before start date of trial

Their attorney need to be very thorough , ethical and crystal clear on these
So does their Chinese interpreter.

There are previous legal cases involved mainland Chinese who so not speak English very well and Chinese interpreters were from
Hong long or Taiwan. The interpreters translated the most critical points in a causal way and Chinese took it as "may be or may not not"

The case went very bad for Chinese