These names are not so much official as they are based on the Unicode standard.
For commonly used characters Glyphs contains definitions for much more compact names, but that approach does not scale well to all of Unicode. However, you can define custom names either using a custom glyph data file
or defining a custom glyph name in a single Glyphs file (Edit → Info for Selection…).
For the most part it should just work. Ensure that the Unicode code point and associated glyph properties (category, case, …) are unchanged after you rename the glyph (viewable in Edit → Info for Selection…).
There might be some extensions or other systems expecting specific names, but that is rare. Once exported, the names are replaced by the production name anyway, so these names are never included in the exported font file.