Them Tag matches were something else.
Force Outs (you'll see those a LOT in the videos) and Tag Bursts have to be performed by the player that is currently not in the match (in the case of two or more players on a team and can only be performed if there are two characters alive on the team).
Force Outs are performed with 236H+P+K and Tag Bursts are performed with 214H+P+K. FO's will not actually Force Out against an airborne foe, it will result in an knockback (1:53 in below video).
Tag Throws can currently only be performed with 66H+P+K, there is no 44H+P+K Tag Throw. If a pair is compatible 66H+P+K will perform their unique throw, if they are incompatible the player performing the throw will throw the grabbed player behind them and the now active player will perform a throw of their own.
Just because a pair has an intro it will not guarantee a Tag Throw (Eliot/Ayane as of the SJ7 build Tom Lee brought with him). They may have a Tag Throw off of a Command Throw but it will take some digging to find it.
Ex. Rig/Christie
Rig can perform his 66H+P+K but it will act like an incompatible pair throw while Christie can perform her Tag Throw and result in a compatible pair (unique Tag Throw).
We didn't check it out but right now it would be safe to assume that there are still compatible command throws outside pairs that do not have a special intro (Bayman/Hyabusa in past iterations).
You can Tag Out while laying on the ground.
I did notice in the Leon/Zack win pose the two seem to be standing too far apart for the "wave" portion of the pose.