How to add XY scale (coordinates) to the mean shape

[ghost]

Could you please help me with how I can add the XY scale to the mean shape? I have used the following codes that provide mean shape but without inside the XY plot. Thanks for the help

`## mean shapes and PCA For side
ms_ <- MSHAPES(eOTO,fac = 'Sex' )
ms_ <- ms_$shp
datams_<-rbind(data.frame(ms_$M, Group="Male"),
data.frame(ms_$F, Group="Female"))

ggplot(datams_)+theme_bw()+geom_path( aes(x,y, color=Group, linetype=Group), size=0.5)+theme_void()+theme(legend.position = c(0.5,0.6), axis.title = element_blank(), axis.ticks = element_blank(), axis.text = element_blank())+coord_equal()+
theme(legend.key.size = unit(5, units = "mm"))
`