My inclination would be to spell the name as JOHANNA. In 1811, maybe JOHANA was a variation in use. But JOHAXA just looks wrong.
Maybe that was her name.
Maybe it was a correction of a mirrored N – similar to Liscleary – but one would expect removal of the incorrect diagonal if that were the case.
If a correction was to be done, I would have expected IHS to have been transformed into HIS.