emboar's stats focuses more on hp, atk and sp.atk stats but bad defense, sp.defense and speed. while samurott has more rounded stats but has nice atk and sp.atk stats
emboar has advantage against burgh, grimsley
samurott has advantage against clay
i dont know if I miss any
well both are nice, I suggest you either use oshawott (rounded stats easier to use for ingame) or tepig (hp, atk, sp.atk harder to use than oshawott)
its up yo you