A new check list 
Are the English and French dictionaries shown in “Tools → Extension Manager” (without any error message)?
(1) Is “English (UK)” shown in in the language field of the “Status Bar” when you open a new empty Writer document?
(2) Menu "Tools → Options → Language Settings → Writing Aids → Available language modules”:
Is “
Hunspell SpellChecker” enabled?
(3) Menu "Tools → Options → Language Settings → Writing Aids → Available language modules → Edit…
→ Language English (UK) / → Language French (France):
Are the English and French dictionaries shown with an “ABC check-mark”?
(4) Is “Spelling
Hunspell SpellChecker” enabled for English (UK) / French (France)?
(5) Menu “Tools → Options → Language Settings → Writing Aids → Options”:
Is “
Check spelling as you type” enabled?
Please, could you upload a sample document (English/French) with the spellcheck issue?