IMO, the banner on the app icon is enough to convey the message that VG has 5v5, but putting 5V5 in the app name as well is kinda off-putting for me because it overly adds clickbait for downloads.
clickbait means something else.
If the name leads to more downloads, you already explained why they will use it in the first place. They want people to know instantly that this game has 5vs5, especially considering it’s an old game that most of the seasoned players will already know and that it doesn’t have 5vs5.