What is the best merc setup for a GF barb?

trav = eth fort, eth andy, eth reaper toll

Ebotd wp, andy, coh

You should ask in D2R Discussion: https://forums.d2jsp.org/forum.php?f=148

But if you want your merc to drop more gold for you, you could use Crown of Thieves, Treachery, and a Polearm of your choosing (I don't recommend Obedience due to its cold damage chance of shattering enemies).

eth arioc's needle

i guess have 2 choices
high dmg, mighty merc, botd/eth reaper/eth needles, gface in cham, fort armor
high gf, eth tomb reaver in lems, cot in cham, wealth armor

Eth tomb reader, eth COT, eth wealth

Depends a little bit on how you play and how good you are at reading the game and shutting down the members.

If you don't want to think, and don't mind losing a bit gold, then reaper's, forti and guillaume's surely is the quickest and safest.

If you can read the game and use war cry intelligently, you can get away with more gold by using ebodt war pike, crown of thieves and wealth. But this requires a very good understanding of how they move and function, as well as great positioning skills and timing.