Jade Mace or Wu's Trance Stick @ 35
 

Once the Wu's stick starts proccing (35) should I switch back to them, or keep my Jade Maces?

Even if you had max dex, bringing your procs to 2 per min, it would still be better to use a jade mace. Also you should get something different for your offhand. The classic JM/Knuckle Duster combo is better than dual maces.

It's not, both weapon have 0.5 ratio and will perform the same in the offhand.

Yep you're right. Not sure why I thought that. Though since they do perform basically the same you can bank some money by selling the JM and getting a KD since it's much cheaper.

Slower is generally better for offhand given equal ratios for less ripostes and less damage shield damage taken.

I'd still probably stick with the jade mace though simply because it will sell much faster and also makes a great twink weapon for below 20 if you ever wanted to make one.

For the classic experience, I recommend Peacebringer til epic and use trance sticks to keep 1h up as you level since they cost like 75pp

IFS