Which is the best trapper for my SPL team on cart?

I have been out of the loop since ORAS and i basically used the standard SPL team where pex used to be tentacruel and dugtrio cresselia.

I hear that trappers are mandatory these days? Why is this?

I see how everyone uses dugtrio but i heard goth was really good back in the day? Which one would be better because i play on cart so i can use either.

I also saw quaqsire over clefable when clefable has wish and heal bell.

This isn't an RMT, i just want to know what is the best trapper on a sableye stall team in general not counting smogons bans.