Phase is in the Ax8, in the Mod tab once you get into the edit page for the delay. Did you ever raise the Mix% like I suggested? I hope so. really sounds like you don't want to|or can't put in the time to learn the simple navigation on the AX8. Please do not take that the wrong way. If you don't or cannot. well. that's that. No crime, no foul. But, It is the same as any other device. Once you learn it you know. When I had a Boss Gt10, it was the same. Until I learned the navigation I was lost. Same with your Zoom I have no doubt. Granted the deeper functions in the axe take some time. But the basic navigation is pretty much like any other device.
Why don't you just try this for now: Using "axe edit" go to the preset you want the delay in. then add the delay, or if already their click on the delay. This will get you to the edit page on the ax8 itself. Then using the page button on the right of the ax8, hit it and you will move thru the tabs. Stop at the mod tab. If you pass the mod tab, keep pressing it will wrap around and you can get to the Mod tab.
Then use the E knob to go up and down. Down you will see what Chris is talking about-the phase parameters and phase rev. You will also see that as you turn the E knob to go down\or up the A_B_C_D letters move with you so you always know which knob will edit the parameter you are on. Try that and please try the Mix%.
Just for a reference. It takes about 5-7 seconds to get to the delay edit screen from the preset default view which is footswitch page. But, you do have to know which buttons\knobs to use. But it's the same for every effect or block. I really do understand the frustration of knowing how to edit your device and trying something new. I used axe edit all the time and never really learned the front panel on the axe fx's I owned. I used to get so pissed trying to use the manual, etc. But once I learned which knob does what, it was a piece of cake.
Whatever you wind up doing is cool-it's about the music and you.....Your a good player obviously so that's what matters. The rest are tools.....