At many schools if you apply as an East Asia Studies major, it will be extremely difficult to switch into CS or even take courses for a minor in CS.
If your goal is CS, apply CS. As to if it’s better to do it through the college of engineering or the college of arts and sciences, depends on your interests and goals. Look up the 4 year plan of study and look at the differences in course work. See what appeals to you the most and then apply. Showing fit is much more important than trying to discern which will be an easier major for admission, especially at your reach schools where admission odds are so low no matter what.
You can also look up the first destination surveys for the colleges on your list and see what the different starting salaries look like for CS in engineering vs arts. I think you’ll find them fairly comparable.