etymology from menapian belgic tribe

hello
i think menapian name is germanic and not celtic < men = man
* men-apii = the man from the sea (the shore < north sea = ap- =
water root)
* men -apii = the man form the moenos river = Main (?)
* men-(n)apii = the thieves

The root IE : Ap = to take/Seize = Ko(m)-ap = couple = to reach
together
Latin H-abere = to possess and R-apere = to take quickly
Grec = Er-eptomai = to devour
Sanskrit = Ap-noti = he reaches
Hittite = Ep-mi = he takes

Or root napi < IE Nakw = thief
Old english = Napand = eager < English Nab/Nap/Kidnap and Nip/Nipper
Danish/Norse = Nappe = to catch/To steal and Suedish = Nappa = to
steal
germain = schanapphahan < french chenapan = thief
latin = nancisci = to obtain
grek = Nike = victory (?)i(m not sure
tchek = Naèapat = to marry/To collect

but the problem in germanic tje word "men" is in second position
like :
marco-mani = the border-man
ala-mani = all the men = the coalition
ger-mani = the howlers (?) the neighbours (?)

what do you think ?