Is memorizing hadith in translation like memorizing it in Arabic?
Question

Is memorizing hadith in Arabic the same as memorizing the translation of the hadith in any other language?
Praise be to Allah.With regard to memorizing and learning the Prophet’s Sunnah, undoubtedly the basic principle is that all of that – for the one who is able – should be done in Arabic, the language in which the revelation came, and in which the hadiths were narrated in the books of Sunnah. This is better than memorizing the meanings translated into other languages, for two important reasons:
The first reason is:
Arabic is one of the symbols of Islam, and it is the language that was chosen by Allah, may He be exalted, to transmit the message of Islam. Whenever the Muslim is able to learn his religion in this language, he should not turn to any other language. This was the view of the righteous early generations.
Ash-Shafa‘i (may Allah have mercy on him) said:
Every Muslim must learn as much of the language of the Arabs as he is able to so that he can testify in Arabic that La ilaha illa Allah wa Muhammad ‘abduhu wa rasuluhu (there is no god worthy of worship except Allah and that Muhammad is His slave and His Messenger), and he can recite the Book of Allah in Arabic, and recite the words of dhikr that he is enjoined to recite, such as takbir, tasbih and the tashahhud, and so on.
The more knowledge he can learn in the language which Allah made the language of the last of His Prophets and in which He revealed the last of His Books, the better it will be for him. End quote from ar-Risalah (p. 48-49).
Shaykh al-Islam Ibn Taymiyyah (may Allah have mercy on him) said:
Ash-Shafa‘i said: … The language which Allah, may He be glorified and exalted, chose was the language of the Arabs, in which He sent down His holy Book, and He made it the language of the last of His Prophets, Muhammad (blessings and peace of Allah be upon him).
Hence we say: everyone who is able to learn Arabic should learn it, because it is the foremost language that one should strive to learn, without forbidding anyone to speak a non-Arabic language.
Ash-Shafa‘i regarded it as disliked for one who knows Arabic to give names in any other language, or to speak it mixed with foreign words. What the leading scholars said concerning this issue was narrated from the Sahabah and Tabi‘in. End quote from Iqtida’ as-Sirat al-Mustaqim (1/521-522).
The second reason is:
Translated hadiths are translations of the meanings, and there are a number of hadiths in which the words are to be pronounced as they are in Arabic, so the one who memorizes them should pay attention to their pronunciation in Arabic as much as he is able, such as the hadiths which mention adhkar. This is indicated by the hadith of al-Bara’ ibn ‘Azib, who said: The Prophet (blessings and peace of Allah be upon him) said:
“When you go to your bed, do wudu’ as for prayer, then lie down on your right side and say: 
Allahumma aslamtu wajhi ilayka wa fawwadtu amri ilayka wa alja’tu zahri ilayka raghbatan wa rahbatan ilayka, la malja’a wa laa manjaa minka illa ilayka. Allahumma amantu bi kitabika alladhi anzalta wa nabiyyika alladhi arsalta (O Allah I submit my face to You, and I entrust my affairs to You, and I rely totally on You in hope and in fear of You. Verily there is no refuge nor safe haven from You except with You. O Allah, I believe in Your Book which You have revealed and in Your Prophet whom You have sent).  
Then if you die during the night, you will have died following the fitrah (sound nature of man). Make these the last words that you speak.” 
He said: I repeated it back to the Prophet (peace and blessings of Allah be upon him), and when I reached the words. “Allahumma aamantu bi kitaabika alladhi anzalta (O Allah, I believe in Your Book which You have revealed),” I said: “Wa rasulika (And Your Messenger).” He said: “No. Wa nabiyyika alladhi arsalta (and Your Prophet whom You sent).”
Narrated by al-Bukhari (247) and Muslim (2710).
Al-Hafiz Ibn Hajar (may Allah have mercy on him) said:
The most appropriate thing that can be said regarding the reason why the Prophet (blessings and peace of Allah be upon him) corrected the one who said “rasul (messenger)” instead of “nabi (prophet)” is that the wording of adhkar is tawqifi [i.e., they can only be known through divine Revelation and sound texts of hadith, with no room for ijtihad or alteration]. They must be recited as the Prophet (blessings and peace of Allah be upon him) recited them, because that pronunciation has special effects and benefits, and they should not be altered. Therefore they must be recited with the same pronunciation that was narrated from the Prophet (blessings and peace of Allah be upon him). This is the view favoured by al-Maziri… End quote from Fath al-Bari (11/112).
With regard to other hadiths, in many cases there is a difference of scholarly opinion regarding their interpretation, so a translation will be based on the meaning favoured by the translator, or on what he understood, which may based on a weaker scholarly view, or it may be based on his own understanding which is incorrect, or it may be incorrectly expressed in the language into which it is translated.
In some hadiths, the Arabic wording may indicate a number of meanings, some of which are lost in translation, so the one who reads the translation understands only one meaning, and if the translator aimed to encompass all the meanings that are contained in the hadith, the translation would be so long that the one who wants to memorize it would tire of it.
But for the one who is not able to learn Arabic or memorize in Arabic, so he memorizes in his own language, he is still doing well. All that he is lacking is the pronunciation in Arabic, but if understands the meaning, this is beneficial knowledge that he has acquired, even if that has to do with adhkar, supplications (du‘a’s), ruqyah and the like. So there is nothing wrong with him offering supplication in translation, and remembering Allah in his language that he is able to speak.
For more information, see the answers to questions no. 262254 and 318586 .
Conclusion:
The one who is able to learn Arabic should study the Prophet’s Sunnah and memorize it in Arabic, with the pronunciation narrated in the books of Sunnah, because Arabic is a symbol of Islam and is the language in which the revelation came.
Memorizing in Arabic means memorizing the pronunciation, and in some cases the pronunciation is essential and required, such as adhkar. That will also preserve the full meanings, some of which may be lost in translation.
And Allah knows best.