Bip39 Checksum. While you'll find BIP39 wordlists in languages apart from English, it's strongly not suggested to make use of non-English words for wallet backups. It might make restoring the wallet hard or extremely hard. BIP39 specifies a list of 2048 words from which the mnemonic phrase is picked out. https://socialbuzztoday.com/story4932393/bip39-https-linktr-ee-bip39-the-fact-about-bip39-words-that-no-one-is-suggesting