What is the English idiom for Russian "режет глаз" which literally translated as "hurts the eye"?

It is an eyesore:

an unpleasant or ugly sight in a public place: They think the new library building is an eyesore.

(Cambridge Dictionary)

It sticks out like a sore thumb.

If you say that someone or something sticks out like a sore thumb or stands out like a sore thumb, you are emphasizing that they are very noticeable, usually because they are unusual or inappropriate.

Does the new housing stick out like a sore thumb or blend into its surroundings?

In Japan a European stands out like a sore thumb.

— collinsdictionary.com

Idiomatically, it may be described by the aural analogue of a jarring note. It strikes a jarring note.

Jarring : jarring sight, sound, or experience is so different or unexpected that it has a strong and unpleasant effect on something or someone

Cambridge

You may consider the opposite of 'easy on the eye', i.. 'not easy on the eye'

But only where the translation has a negative component in the expression

Easy on the eye (informal) Pleasant to look at.

1. Soft colours are easy on the eye.
2. Her paintings are very easy on the eye.
3. The room was painted in soft pastels that were easy on the eye.
4. And frankly, she's pretty easy on the eyes, too.
5. It was vital that they should be prompt and professional as well as easy on the eye.
6. Garda Garda is a charming old village that is very easy on the eye.
7. Above all,[http://sentencedict.com/easy on the eyes.html] it should be as physically comfortable and relaxing as it is easy on the eye.

https://sentencedict.com/easy%20on%20the%20eyes.html

This idiom originated around the year 1900. People typically use it to describe a person who is beautiful or handsome. The idea behind this expression is that someone who is attractive is easy to look at. Conversely, something that is ugly is hard to look at.

https://writingexplained.org/idiom-dictionary/easy-on-the-eyes

The idiomatic expression you are looking for is:

It is painful to look at.

This is clearly closer to the literal meaning of the idiom you wanted to translate, than "sore thumb", though it is pretty similar to "eyesore". So you could use either one depending on the grammatical structure you want to have at that point.