By default, Algolia normalizes all characters to their lowercase counterparts and strips them from their diacritics. You can prevent this behavior using the keepDiacriticsOnCharacters setting.
This option is available to change on the index Configuration page in the Dashboard.
However, please note that this could have an effect on search as if you turn this feature on for certain diacritics, then when users search without these diacritics it may return less results.