No, that’s too complicated. I would keep the icons and simply switch the names:
In all applications I know – e.g. Numbers, Pages, Excel, graphic applications – “center horizontally” means move things horizontally from left to right or vice versa (to reach a common vertical axis). “Center vertically” means move things up and down (to reach a common horizontal axis).
Or you use the same nomenclature as in Panorama 6: Under the title “Align Objects”, these two options were named “R/L Centers” and “T/B Centers”.