I read this example sentence in Oxford Advanced Learner's Dictionary:
Such is the elegance of the typeface that it is still a favourite of designers.

At first sight, I thought it was an inversion of the sentence
The elegance of the typeface is such that it is still a favourite of designers.

But now I think they don't mean the same.

"Such" in the original sentence is used to emphasize the degree of "elegance" -- the typeface was so elegance that designers still like it -- while "such" in the latter means 'of the type that you are just going to mention' (Oxford Advanced Learner's Dictionary) -- the elegance of the typeface is one of the kinds that designers like.

Is "such" the subject of the original sentence?
Can you please make a few more sentences of such a structure (Such + be + something + that clause) for me to understand it better?

Question

I read this example sentence in Oxford Advanced Learner's Dictionary: 
Such is the elegance of the typeface that it is still a favourite of designers.

At first sight, I thought it was an inversion of the sentence
The elegance of the typeface is such that it is still a favourite of designers.

But now I think they don't mean the same.

"Such" in the original sentence is used to emphasize the degree of "elegance" -- the typeface was so elegance that designers still like it -- while "such" in the latter means 'of the type that you are just going to mention' (Oxford Advanced Learner's Dictionary) -- the elegance of the typeface is one of the kinds that designers like.

Is "such" the subject of the original sentence?
Can you please make a few more sentences of such a structure (Such + be + something + that clause) for me to understand it better?

Answer

I think you're overthinking it.  You were right the first time.

The typeface was so elegant that designers still like it.   And IT refers to the typeface, not elegance.

No one would interpret this to mean:  designers like some kinds of elegance, but not others.

Answer

There is no difference between the two sentences. Let's analyze.

Both are compound sentences. That is, each sentence is really two sentences joined by the conjunction "that":

"Such is the elegance of the typeface" is a complete sentence.
"It is still a favourite of designers." is a complete sentence.

"The elegance of the typeface is such" is a complete sentence.
"It is still a favourite of designers." is a complete sentence.

So, in reality your question only asks to compare the sentences
"Such is the elegance of the typeface."
"The elegance of the typeface is such."

There is no difference between these two sentences. Zero. The placement of the pronoun "such" changes nothing whatsoever.

Answer

They have the same meaning ;  you could think of  'such'  in this context as being  'so much' or 'so great'.  Both forms are used and they are equally good.

Answer

You are correct in your interpretation of the two sentences. In the original sentence, "such" is used to emphasize the degree of elegance, while in the latter sentence, "such" means "of the type that you are just going to mention".

In the original sentence, "such" is not the subject, but rather it functions as a determiner that modifies the noun phrase "elegance of the typeface". The subject of the sentence is "it", which refers to the typeface.

Here are some more examples of sentences with the structure "Such + be + something + that clause":

Such was the intensity of the storm that many houses were destroyed.
Such is the popularity of the band that tickets for their concert sold out within minutes.
Such is the complexity of the problem that it will take a team of experts to solve it.
Such is the importance of education that governments around the world invest heavily in it.
Such is the skill of the chef that his restaurant has received numerous awards.