The crossover movie's planning is led by the current production, so the villains will be created by Zero One's team. They could go with an Another Rider, but considering Heisei Generations & Final, I think it's more likely they'll go with a villain they can actually tie into Zero-One's series itself.

Maybe the main villain is one of MetsubouJinrai.NET terrorist who come from future and he will become Another Zero-One....

And, hopely Sougo can use Zero-One Ridewatch to access Zi-O Zero-One Armor...

I still really want some of Legend Heisei Riders will be appeared in the movie....

Sixth Rider?

https://akkinews.net/archives/208456

Hmm...he more likely are from other company. Maybe his company are Android producer too just like Hiden Intelligence.

It's really hitting me now just how many Riders Zero-One will potentially have. We've got the five confirmed from the start; but then there's the Q2 belt that that above likely points to; then the Q3/4 retool/recolour belt; then likely a summer movie-exclusive rider...

And then you realise this all makes sense when Ex-Aid had around 8 riders itself. This could be the most Riders we've had since then.

There isn’t always a third-quarter belt/Rider, though. Zi-O didn’t have one, nor did Ghost.

Ghost did have one, it was just a bit more unconventional than usual -- rather than being a new rider, it was the belt he used for Grateful. Ghost as a series saw three belts at retail; the Ghost Driver, the Necrom Driver, and the Grateful driver. It's clearly something that they decided against doing again because I can't think of any other time since or even before where an upgrade for the main rider was through a new belt, thus I think we can safely assume it'll be new riders for Q3 belts from here on out, as was the case for Ex-Aid and Build.

Zi-O is definitely an interesting exception... at retail. But we've seen not just one but TWO belts as Premium Bandai exclusives -- the Mirai Rider Driver and the Oma Zi-O Driver, both of which are relevant to characters in the show. So I feel safe in saying that the trend will continue in some form.

Oh shit yeah! Forgot about that.
Necrom's Mega Ulorder wasn't a belt, though :P
I understand what you're getting at, though!

However...they are in no way the same thing, seeing as the Mirai Driver went up for order in the Second Quarter (like the Proto-Mega Ulorder or the Para-DX Buckle) and the Oma Zi-O Driver at the end of the show (making it the same thing as the Bannou Driver). Neither were used by permanent main cast members either.
Having big third-quarter belts seems to be something they cycle on. We had the White Wizard Driver...but then nothing until the Eyecon Driver-G (though we did get the Signal Axe for Chase in Drive). This was then followed by the Buggle Driver II and the Evol Driver...but nothing in Zi-O.
Personally, I hope we do get a Third-Quarter belt, I just don't think it's as certain as one in the Second-Quarter is.

That's true! But my point was purely that it would be another rider; even if they get as much screentime as Scissors or Quiz.

Though... yeah, either way, the Zi-O situation is odd as it's been a standard since Drive (and W and Wizard done it prior). I can only imagine it was because of how much legacy stuff they were putting out; compared to even Build or Ex-Aid the Ridewatch train just refused to stop.

Oh, I see! I apologize - I thought you were saying that there would definitely be a bid Third-Quarter belt because it's an iron-clad tradition, which is what I held issue with.

It should be as well, though, that Chase reused the Mach Driver Honoh without alteration, and just got a weapon to come with his trinket - which is one way they could have a seventh rider but reuse the Shot Riser, Force Riser, Zero-One Driver or, assuming that post is true, the ThousanDriver.

Zi-O's third quarter is perplexing though. It was unusually barren, and very little made it to mass retail. IIRC, it just the Grand Zi-O and Woz Ginga Ridewatches.