How to translate "很不起眼儿" in English

Question

What's the best (传神) translation of "很不起眼儿" in English?

例句：

不认识他的人觉得他很不起眼儿，认识他的人觉得他很优秀。

辨析：

A more formal term that related to "很不起眼儿" is "其貌不扬", but
"其貌不扬" will normally be "很不起眼儿", yet "很不起眼儿" does not necessarily means "其貌不扬". So the side question is,

How to translate "其貌不扬"?

UPDATE

Thank you for the answers, by 传神 translation, I meant to ask what people would say in their daily expressions...

"他很不起眼儿", my closest English translation is "He's quite a normal Joe", but "很不起眼儿" is a bit stronger than that

Answer 1

my preference: "很不起眼儿" can be translated into “unimpressive”,while "其貌不扬" into "unimpressive-looking". The reason is that "unimpressive" can refer to many aspects such as his appearance, his achievement, and etc. Compared with"很不起眼儿", ""其貌不扬"is more specific to the appearance, so "looking" is added to "unimpressive".

Answer 2

ABC: inconspicuous; not striking; unremarkable

A Chinese-English Dictionary: DIALECT not attract attention; not be noticeable; not be attractive

这座厂房并不起眼, 但产品却是第一流的。 Zhè zuò chǎngfáng bìng bù qǐyǎn, dàn chǎnpǐn què shì dì-yī liú de. The factory building doesn't attract much attention, but the products are first-class.

别看这人不起眼儿, 人家可是一肚子学问。 Bié kàn zhè rén bù qǐyǎnr, rénjia kěshì yī dùzi xuéwen. He is not taken much notice of, but he is a very learned man.

ADS: not to draw the eye

CC: 1 unremarkable 2 nothing out of the ordinary

KEY: inconspicuous, unremarkable, plain, modest, unassuming

Oxford: Nondescript

Oxford Pocket; Not noticable / not attractive

1. 其貌不扬

ABC: be homely/unprepossessing

A Chinese-English Dictionary: be unprepossessing (or unimposing) in appearance; be of undistinguished appearance

Oxford: of undistinguished appearance

别以为他其貌不扬就小看他。 Don't slight him just because he is unimposing in appearance.

KEY: of undistinguished appearance

Answer 3

I agree with you that the English classification you are using is not accurate because the strong negative inference is lost. 不起眼 represents the outer idea:

but just taking 起眼 shows the highly negative implication of the main term:

Therefore as you've noted, the English term is much softer than Chinese term used in this case. Regarding your side question, 其貌不扬 seems to be "homely":