I'm not sure if that is solvable. Could you create an issue on the jooa11y main tracker please https://github.com/joomla-projects/joomla-a11y-checker/issues

@dyfrig Make it easier. For example, how we did it for the Russian language, since we also have enough forms of pluralization.

https://github.com/JPathRu/localisation/blob/joomla-4/administrator/language/ru-RU/plg_system_jooa11y.ini#L51

never use a _figure=" when it is NOT a plural form!!!

Rather use for example
PLG_SYSTEM_JOOA11Y_PANEL_2_STATUS="1 accessibility error and %(warningCount) warnings found."

I would suggest combining Kostelano's and Infograf768's suggestions into to avoid both problems. Not sure if it would work for all languages but it would for Welsh and, according to Kostelano for Russian. This would result in something like

;Panel status
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_1_MESSAGE="Accessibility errors: 1, Warnings: 1"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_10_MESSAGE="<span class="jooa11y-visually-hidden">Warnings found: %(warningCount)"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_11_MESSAGE="<span class="jooa11y-visually-hidden">total issues found: %(totalCount)"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_2_MESSAGE="Accessibility errors: 1, Warnings: %(warningCount)"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_3_MESSAGE="Accessibility errors: %(errorCount), Warnings: 1"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_4_MESSAGE="Accessibility errors: %(errorCount), Warnings: %(warningCount)"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_5_MESSAGE="Accessibility errors: 1"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_6_MESSAGE="Accessibility errors: %(errorCount)"
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_7_MESSAGE="Please review warning."
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_8_MESSAGE="Please review warnings [%(warningCount)]."
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_9_MESSAGE="No accessibility errors found."
PLG_SYSTEM_JOOA11Y_PANEL_STATUS_12_MESSAGE="The item you are trying to view is not visible; it may be hidden or inside of an accordion or tab component. Here's a preview="

I'm not sure if that is solvable. Could you create an issue on the jooa11y main tracker please https://github.com/joomla-projects/joomla-a11y-checker/issues

Done joomla-projects/joomla-a11y-checker#66

As this will require changes upstream first and as @dyfrig has created an issue there can this be closed here.

Closing the issue as the upstream includes both original issue and Infograf768's comments.