Mitai vs No you?
Konnichiwa! I don't understand the difference between MITAI and NO YOU/ YOU NI MIERU

Could someome explain the difference between these two possible sentences for me?

Tanaka-san wa hashitte iru mitai desu
Tanaka-san wa hashitte iru you ni miemasu (/ hashitte iru you desu?)

Onegaishimasu!

Question

Mitai vs No you?
Konnichiwa! I don't understand the difference between MITAI and NO YOU/ YOU NI MIERU

Could someome explain the difference between these two possible sentences for me?

Tanaka-san wa hashitte iru mitai desu   
Tanaka-san wa hashitte iru you ni miemasu      (/ hashitte iru you desu?)

Onegaishimasu!

Answer

"Mitai" and "you" means the same.
They are 90% interchangeable.

*** What is "you"

It is 様（you), a Chinese-originated word, which means "appearance"

*** What is "mitai"

It is a broken sound of "MITA-YOU-NA",
which consts of "見た（saw/looked), 様(appearance), な".

Here you can see the word "様“ is included.

**** Gererally "you" sounds  more formal than "mitai".

It is because "you" is Chinese-oriented(音読み） and "Mita" in "Mitai" is Japanese own word（訓読み）. The imported Chinese words are generally regarded as of formal use. It is like the relation between Latin-originated words and its own words in English.