I can type 0.; but no .0, nor comma or whatever symbol that could be a wildcard.
If a type 0 or a, and to the left I type a dot, the name field is emptied.
Version: 7.4.7.2 (x86) / LibreOffice Community
Build ID: 723314e595e8007d3cf785c16538505a1c878ca5
CPU threads: 4; OS: Windows 6.1 Service Pack 1 Build 7601; UI render: Skia/Raster; VCL: win
Locale: es-MX (es_MX); UI: en-US
Calc: threaded
EDIT: The same with:
Version: 7.6.0.2 (x86) / LibreOffice Community
Build ID: 41d6f628ba3f046f16b5fa9fa8db8d4c2ab3b582
Maybe you must restart in safe mode to test.
EDIT pasted frome comment below, that was changed with Linux info:
If I set the locale to Spanish (Mexico) (dot as decimal separator) I can set field names with 0. or a., but not with 0, or a,.
If I set the locale to Spanish (Argentina) (comma as decimal separator) I can’t set field names with 0., 0,, a. or a,.