Language/Multiple-languages/Culture/Licensed-Free-Databases
The listed are databases, not applications. That is to say, if you don't know programming, maybe they won't help you so much.
Multiple languages
https://unicode.org/ucd/
License address: https://www.unicode.org/copyright.html
Some of its users: Gucharmap, decodeunicode
Unicode.
https://dumps.wikimedia.org/
License address: https://dumps.wikimedia.org/legal.html
Some of its users: Wikimedia
Wikimedia.
https://iate.europa.eu/download-iate/
License address: https://iate.europa.eu/download-iate/
Some of its users: IATE
Terminology dictionary of the EU.
https://tatoeba.org/eng/downloads/
License address: https://tatoeba.org/eng/downloads/
Some of its users: Tatoeba, ListeningPractice.org, Jisho.org
Parallel corpora. In common words, collections about a sentence in different languages.
http://www.gutenberg.org/wiki/Gutenberg:Information_About_Robot_Access_to_our_Pages
License address: http://www.gutenberg.org/wiki/Gutenberg:Terms_of_Use
Some of its users: Gutenburg Porject, LibriVox
Ebooks.
https://librivox.org/pages/about-librivox/
License address: https://librivox.org/pages/about-librivox/
Some of its users: LibriVox, ListeningPractice.org
Audio books
http://www.dicto.org.ru/xdxf.html
License address: http://dicto.org.ru/license.html
Some of its users: Dicto
Dictionaries.
http://www.omegawiki.org/Help:Downloading_the_data
License address: http://www.omegawiki.org/Meta:Main_Page
Some of its users: OmegaWiki
Dictionaries.
http://compling.hss.ntu.edu.sg/omw/
License address: http://compling.hss.ntu.edu.sg/omw/
Some of its users: Open Multilingual Wordnet
Wordnets.
http://shtooka.net/download.php
License address: http://shtooka.net/
Collections of audio.
https://en.wiktionary.org/wiki/Wiktionary:Frequency_lists
License address: https://en.wiktionary.org/wiki/Wiktionary:Frequency_lists
Frequency lists.
https://lego.linguistlist.org/about#contact
License address: https://lego.linguistlist.org/about#copyright
Some of its users: LEGO
Lexicon. No download link on the website.
https://panlex.org/source-list/
License address: https://panlex.org/license/
Some of its users: Glosbe
Lexical database links.
http://cjklib.org/0.3/
License address: http://cjklib.org/0.3/
Some of its users: Make Me a Hanzi
Data about Han script.
https://iso639-3.sil.org/code_tables/download_tables/
License address: https://iso639-3.sil.org/code_tables/download_tables/
Some of its users: SIL, Polyglot Club
ISO 639-3 tables. It assigns each language a code and is updated every year.
https://www.unece.org/cefact/locode/welcome.html
License address: https://www.unece.org/cefact/locode/locode_since1981.html
UN/LOCODE, an alternative to ISO 3166-2. It is updated twice a year.
https://www.geonames.org/
License address: https://www.geonames.org/
Gazetteer and postal code data for free. I wonder if it should be in “multiple languages”.
https://www.unicode.org/iso15924/codelists.html
License address: https://www.unicode.org/copyright.html
Some of its users: Unicode
ISO 15924 lists. Codes for scripts.
https://help.archive.org/hc/en-us/articles/360017781111-How-to-download-files-
License address: https://www.archive.org/about/terms.php
Some of its users: Internet Archive
Archived Internet content.
Japanese
http://www.edrdg.org/wiki/index.php/Main_Page
License address: https://www.edrdg.org/edrdg/licence.html
Some of its users: Jisho.org, Tagaini Jisho
Japanese dictionaries.
https://kanjivg.tagaini.net/
License address: http://kanjivg.tagaini.net/
Some of its users: Tagaini Jisho, Jisho.org
Kanji strokes.
https://joyokanji.info/
License address: http://www.bunka.go.jp/bunkacho_homepage/index.html, http://www.mext.go.jp/b_menu/about_link.htm, http://www.moj.go.jp/term.html
Some of its users: 常用漢字情報サイト
Jōyō Kanji, Jinmeiyō Kanji, Kyōiku Kanji in a easy-to-copy form.
Chinese
https://resources.publicense.moe.edu.tw/index.html
License address: https://resources.publicense.moe.edu.tw/index.html
Some of its users: 教育部國語辭典公眾授權網, 萌典
Dictionaries of ROC Mandarin Chinese written in ROC Mandarin Chinese.
https://cc-cedict.org/editor/editor.php
License address: https://cc-cedict.org/wiki/
Some of its users: MDBG, Pleco
Mandarin-English dictionary.
https://chine.in/mandarin/dictionnaire/CFDICT/
License address: https://chine.in/mandarin/dictionnaire/CFDICT/
Some of its users: Chine Informations, Pleco
Mandarin-French dictionary.
http://www.handedict.de/chinesisch_deutsch.php
License address: http://www.handedict.de/chinesisch_deutsch.php?mode=dl&sid=51394be2b6d9cba75946e929b5477d55
Some of its users: HanDeDict, Pleco
Mandarin-German dictionary.
https://chdict.zydeo.net/en/download/
License address: https://chdict.zydeo.net/en/download/
Some of its users: CHDICT
Mandarin-Hungarian dictionary.
http://cantonese.org/download.html
License address: http://cantonese.org/download.html
Some of its users: CC-Canto, Pleco
Cantonese-English dictionary.
https://twblg.dict.edu.tw/holodict_new/compile1_6_1.jsp
License address: https://twblg.dict.edu.tw/holodict_new/compile1_6_1.jsp
Some of its users: 臺灣閩南語常用詞辭典, 萌典
Taiwanese-Endlish dictionary. It can be requested through email.
http://www.taiwanesedictionary.org/
License address: http://www.taiwanesedictionary.org/
Taiwanese-English dictionary.
http://lingua.mtsu.edu/chinese-computing/
License address: http://lingua.mtsu.edu/chinese-computing/copyright.html
Frequency lists.
Korean
https://github.com/libhangul/libhangul/blob/master/data/hanja/hanja.txt
License address: https://github.com/libhangul/libhangul/blob/master/data/hanja/hanja.txt
Words in Hangul and Hanja.
There is a page of introduction: https://wiki.kldp.org/wiki.php/libhangul.
https://ko.wiktionary.org/wiki/%EB%B6%80%EB%A1%9D:%ED%95%9C%EB%AC%B8_%EA%B5%90%EC%9C%A1%EC%9A%A9_%EA%B8%B0%EC%B4%88_%ED%95%9C%EC%9E%90_1800
License address: http://www.suneung.re.kr/sub/info.do?m=0601&s=suneung
Hanmun gyoyukyong gicho Hanja in a easy-to-copy form.
Esperanto
http://reta-vortaro.de/tgz/index.html
License address: http://reta-vortaro.de/tgz/index.html
Some of its users: Reta Vortaro, PReVo
Dictionary in several languages.
Vietnamese
http://www.informatik.uni-leipzig.de/~duc/Dict/install.html
License address: http://www.informatik.uni-leipzig.de/~duc/Dict/install.html
Some of its users: TuDienHND
Dictionaries in several languages.
There is a page of introduction: https://vi.wiktionary.org/wiki/Wiktionary:Ngu%E1%BB%93n_g%E1%BB%91c/FVDP
American Sign Language
http://www.asl-lex.org/
License address: http://www.asl-lex.org/
Lexicon.