Ah didn't realize these were all FTP.
Yeah, that's what they've got going for them. And aside from Battlecry, the other games have these colorful cartoony looks to them which I mean, is appealing of sorts. And depending on what systems they have for monetizing the game, it can be successful. Let's look at League and DotA-DotA allows you to gain cosmetics in game whilst also selling cosmetics as their primary offering. Riot is a bit more lucrative, they sale champions for both in game currency and money, creating a sort of investment feeling for many people who spend any amount of time in that game. They sale a plethora of cosmetic skins as well, unlike DotA they don't offer any 'in-game drops' from these cosmetics.
If these moba shooters whatever the fuck duval is peddling is able to copy that, and they're able to get a good base of people playing, they have infinite potential. If they don't.....then they'll die out. It seems they all cropped up around the same time, Gigantic/BattleBorn seem to be going for the 'moba shooter' concept, whilst Battlecry/Overwatch is more of the 'team shooter' that TF2 revolutionized wayback when.
As for my bets on who will be 'victorious'....Overwatch has the Blizzard pedigree for it, it has the art style and seems to offer substantial gameplay opportunities with it's 'hero' characters. Battlecry...seems to be alot like TF2 in vain but each faction has different classes...but it loses points for it's look and well, how it looks. Battleborn and Gigantic...I haven't seen any gameplay of it. Battleborn looks....standard. Kinda like Overwatch in its concept of character picks, but it doesn't look that promising.
If I were to take a guess, I'd say Overwatch would win out. Gigantic has that dark horse feel because it'll launch on Xbox as well and it does have a pretty artstyle. Battleborn...well...I don't really see any hype around this game. Dunno if it's launching on consoles, but I'd rather play Gigantic if I was forced to choose(Gearbox doesn't give me hope for the gameplay. Borderlands is fun for the looting and RPG aspects, but the shooting is bland.).
Overwatch will definitely win out in this..moba...shooter fest. Gigantic and Battleborn...my votes for Gigantic. Battlecry will be dead on arrival.