I remember that on the Japanese broadcast there was a segment talking about how JoxJo is the igl, but during Masters on the English broadcast they kept saying that Xnfri is the igl so I wasn't sure.

If Xnfri joins I guess Laz could go back to calling.

I agree with everything he said.
Dep/Laz/Sugarzero are unquestionably the best in their roles in Japan.

Tennn could possibly be upgraded, with Meiy/Xnfri being the only players I'd really consider. (It won't happen as Zeta literally chose Tennn over Meiy when both became free agents after leaving Northeption).

While Crow is the glaring weakspot of the team, it's hard to replace him for two reasons.

1. He is the IGL and long time support player for the team
2. There is a significant lack of top initiator players in Japan, probably the weakest role. Any pick up would be a marginal upgrade at best.

The one exception would be Xnfri, who is an IGL /initiator, albeit with limited reps on Sova/Fade. He could technically being a 1 for 1 replacement for crow.

With that said I expect that Xnfri will be the core player that Detonation builds around, and they'll throw the bag at him.

It'll be difficult to navigate. Some of the Russian players who play for Japanese teams for example would be a curious case.

Does anyone know where Japanese fans have like post-match discussion threads?

It's unfortunate that TakeJ had to be removed for alting, cause he surely belongs on some form of JP super team.