This really depends on how your child’s English standard is. If it is good, then you will have less of a problem. But I believe that some of the schools still want to see his G8 transcript so it might not be that easy to skip a class to G9.

Yes your child will be too old. Schools do not want to see students that are that much older than their peers. You can be a few months old than 15 years old when you enter G9, but not too much more. However you should also ask the school about this when you apply as different schools have different requirements.

I recommend that you go to a less competitive US school this year to study G8. That way you can improve on the English more quickly than if your child stayed in China, even at an international school.

从您的描述来看，为了适应而重读7年级并且跳过8年级并不是很值得。
是否考虑在普通高中读八年级然后申请九年级同时加强英语呢？

没有8年级记录，直接申请美国读9年级，可能有问题。建议在国内读完8年级，再申请美国的9年级。大多数留学生都是9升9。

14岁才读7年级有点晚，美国不会无故让你申请跳级的，如果不想冒险，还是读8年级吧。

就学校而言，加州的学校对学生的年龄限制多一些。如果去读国际班7年级，在未来是否考虑8申9或9申10也是同样的道理呢？（不好意思我逻辑有些混乱，可能我没有特别理解您的问题）

这位家长，上美国高中不是按照年龄来申请的，一般毕业不超过19岁。所以年龄不是问题。
美国高中一般接受的8申9或者9申9。其实国际学校和国内普通高中申请都在同一个池子里，申请主要是看孩子个人的资质，但是在申请时候一定要解释清楚为什么我是7申请9。