The styles selection is always in English (e.g. "Accent, Heading"), no matter what language is set for the user interface. I tried German and French and it seems that there is either a bug in the code not using the translations or that there are no translations - which would be quite a regression. I confirmed this on both Linux and Windows.
This appears to be a regression from along the lines of commit 7b0aed617f1e57335837cf56ef2d222a96f8270d CommitDate: Wed Sep 28 11:42:56 2016 +0000 Remove old cell styles from calc and commit 06f319937187f76ee402d53b3baa78c391c2af19 CommitDate: Sun Oct 2 13:51:26 2016 +0000 tdf#90937 Add a set of cell styles to calc where we now have translatable strings not matching the internal style names anymore.
Taking.
*** Bug 137226 has been marked as a duplicate of this bug. ***
Eike Rathke committed a patch related to this issue. It has been pushed to "master": https://git.libreoffice.org/core/commit/4a3466851c22920aa57443cb31b8f0c57d6c73ce Resolves: tdf#137370 Re-enable UI translated standard cell style names It will be available in 7.1.0. The patch should be included in the daily builds available at https://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More information about daily builds can be found at: https://wiki.documentfoundation.org/Testing_Daily_Builds Affected users are encouraged to test the fix and report feedback.