Google Translate your strings.xml updates to all languages in your project

1. clone
2. put file with text to be translated in file named input.xml
3. run ./translate_all.sh /path/to/your/project/src/main/res - it will get list of languages by searching folders matching strings-b+XX pattern
4. paste contents of translated strings_XX.xml files to the files you maintain the translation
5. profit!

Requires python3

Command line args

translate_all.sh pathToRes sourceLang inputXmlFile

pathToRes      full path to /path/to/your/project/src/main/res of your project (a folder where all strings-b-* folders are located)
sourceLang     language considered as being used in input file. Defaults to en
inputXmlFile   path to file containing source strings to be translated. Defaults to input.xml 

Language codes for reference

Reference only, check google translate page before use.

#   af          Afrikaans
#   ak          Akan
#   sq          Albanian
#   am          Amharic
#   ar          Arabic
#   hy          Armenian
#   az          Azerbaijani
#   eu          Basque
#   be          Belarusian
#   bn          Bengali
#   bh          Bihari
#   bs          Bosnian
#   br          Breton
#   bg          Bulgarian
#   km          Cambodian
#   ca          Catalan
#   chr         Cherokee
#   ny          Chichewa
#   zh          Chinese (Simplified)
#   co          Corsican
#   hr          Croatian
#   cs          Czech
#   da          Danish
#   nl          Dutch
#   en          English
#   eo          Esperanto
#   et          Estonian
#   ee          Ewe
#   fo          Faroese
#   tl          Filipino
#   fi          Finnish
#   fr          French
#   fy          Frisian
#   gl          Galician
#   ka          Georgian
#   de          German
#   el          Greek
#   gn          Guarani
#   gu          Gujarati
#   ht          Haitian Creole
#   ha          Hausa
#   iw          Hebrew
#   hi          Hindi
#   hu          Hungarian
#   is          Icelandic
#   ig          Igbo
#   id          Indonesian
#   ia          Interlingua
#   ga          Irish
#   it          Italian
#   ja          Japanese
#   jw          Javanese
#   kn          Kannada
#   kk          Kazakh
#   rw          Kinyarwanda
#   rn          Kirundi
#   kg          Kongo
#   ko          Korean
#   ku          Kurdish
#   ky          Kyrgyz
#   lo          Laothian
#   la          Latin
#   lv          Latvian
#   ln          Lingala
#   lt          Lithuanian
#   lg          Luganda
#   mk          Macedonian
#   mg          Malagasy
#   ms          Malay
#   ml          Malayalam
#   mt          Maltese
#   mi          Maori
#   mr          Marathi
#   mo          Moldavian
#   mn          Mongolian
#   ne          Nepali
#   no          Norwegian
#   nn          Norwegian (Nynorsk)
#   oc          Occitan
#   or          Oriya
#   om          Oromo
#   ps          Pashto
#   fa          Persian
#   pl          Polish
#   pa          Punjabi
#   qu          Quechua
#   ro          Romanian
#   rm          Romansh
#   ru          Russian
#   gd          Scots Gaelic
#   sr          Serbian
#   sh          Serbo-Croatian
#   st          Sesotho
#   tn          Setswana
#   sn          Shona
#   sd          Sindhi
#   si          Sinhalese
#   sk          Slovak
#   sl          Slovenian
#   so          Somali
#   es          Spanish
#   su          Sundanese
#   sw          Swahili
#   sv          Swedish
#   tg          Tajik
#   ta          Tamil
#   tt          Tatar
#   te          Telugu
#   th          Thai
#   ti          Tigrinya
#   to          Tonga
#   tr          Turkish
#   tk          Turkmen
#   tw          Twi
#   ug          Uighur
#   uk          Ukrainian
#   ur          Urdu
#   uz          Uzbek
#   vi          Vietnamese
#   cy          Welsh
#   wo          Wolof
#   xh          Xhosa
#   yi          Yiddish
#   yo          Yoruba
#   zu          Zulu

Original author's file-by-file translation tool is available online