you can get h1 as long as the job is inline with ur degree(either of them)

theoretically you should work in the field for which your opt is approved for. however, in reality, ead is an ead. you can work for anybody.

如果用opt干根opt领域不一致的工作，是不是算违法啊？

=> nobody will know, really

如果不用opt直接办h1，可行性高吗？

=> yeap. but u have to wait if no quota's available. if u have opt already, why not use it. it will be wasted anyway.