Despite President Trump’s statement that he might intervene in a criminal case against the chief financial officer of Huawei Technologies Co., such a move would break from longstanding tradition and advisers have warned him that his options are limited, according to people familiar with the matter.

When news broke last week of the arrest of Meng Wanzhou, threatening the president’s trade talks with China, he asked for options, according to one person, and advisers told him the arrest and potential prosecution of Ms. Meng was...