What is Handshake Tag in Project L and how will it work?

sportskeeda.com:

Project L, Riot Games’ upcoming fighting game, gets more and more interesting with each day. The developers of this 2 vs 2 fighting game provided us with some new information on how assist functions will work, from Assist Actions to tagging in and out.

Assist Actions, Handshake Tag, and Dynamic Save are three mechanics that have been discussed recently, and perhaps the most interesting of them is Handshake Tag. It’s more than simply tagging in your secondary character at a critical moment; Project L’s Handshake Tag will allow players to extend their combos in crazy ways, providing they can land the timing and execution of this critical maneuver. What is it, though, and how can you put it to use in Project L?

There are three primary mechanics that were focused on by the developers. Assist Actions bring your ally in to deliver attacks while your point character is already in play. This will go hand-in-hand with the Handshake Tag mechanic.

The developers introduced it as a rather simple concept, but using it efficiently is another matter entirely. In Project L, Handshake Tag is a method of swapping characters as long as both are on the screen. To do this, you’ll likely use an Assist Action, and during it, cancel into the Handshake Tag before that character leaves the screen.

If it sounds a little familiar, that’s because it has already been implemented in a few other fighting games, such as BlazBlue: Cross Tag Battle and Power Rangers: Battle for the Grid. Marvel vs. Capcom: Infinite also uses this form of tag, where it is known as an "active tag."

What makes this tag system interesting in Project L is how huge the window is for going from Assist Action to Handshake Tag. Even if, say, Jinx is done using her attack and is posing