on paper

judging something by how it has been planned rather than how it really works in practice

据书面材料，在书面上，在理论上

The design certainly looks good on paper.

该设计从理论上看的确很不错。

Several candidates seemed suitable on paper but failed the interview.

有几个应聘者从申请表上看条件不错，但面试都未通过。