So you are telling us that China doesn't have the technology to stop a moving ship without shooting at it? This should be #1 research priority because it will be useful in all kinds of future maritime conflicts.
Are you telling me you don’t know enough about naval tech and even basic physics to know that no one has such StarkTech McGuffins that can alter fundamentals rules of physics and make hundreds to thousands of tons of ship just magically stop moving even as it’s crew redlines the engines trying to get away, and all while being less violent than using water cannons to shoo them off?
China’s priority is in keeping grew zone intruders out of its waters. It doesn’t want nor need to catch them. Just shooing them off is more than sufficient.
Boarding would be a significant escalation even if you did have magical tech to be able to do it with zero risk of injury or death to the crews. In reality, boarding is a highly dangerous and violent act, and if the crew resists, there will be causalities. That is why boarding ships is such a big deal and not to be done lightly.