bvc axe want to know how work ww now

If you have a slow weapon, you're not going to reach the 4 frame WW BP. Outisde IAS [IAS that is not on the weapon itself] has no effect on the speed of your WW. This includes things such as IAS jewels socketed in your helm, and the Fantaticsm aura from your Beast.

Since you'll be using a Berserker Axe as the base for your Grief, you will need at least 34 IAS [the Berserkers Axe base speed is 0, meaning that you need it to reach -34 speed] in order to hit the 4 Frame [the last, also] breakpoint. Essentially this will mean that you will be hitting more often per second than if you hit a lower BP.

Your offhand weapon [the weapon that your equip last, this means you always want to equip your Grief FIRST, then your beast/doom/whatever] must also reach 34% IAS, but since all the off-hand weapons you should be using [Doom/Beast] already have at least 40%~ IAS, it's not something to worry about.

this is outdated since patch 2.4.3, which went live half a year ago...
ias of different combinations may be testes here: https://warren1001.github.io/IAS_Calculator/