If I am not wrong, in past partnerships and shirts for Flamengo, Watford, Sportsbet does not have big logo on it. It is either on shoulder, sleeve or in front at chest area. Logo is at a size that is recognizable enough but not too large.
In some interviews, press conferences, I see Sportsbet.io logo too.
Arsenal is one of biggest clubs in England and if Sportsbet.io can make a deal to deploy their logo on Arsenal skirts, marketing effects will be very massive. It would be bigger than what they got from partnership with Watford.
It doesn't matter though about the logo, big or small people will see it, I think even Barca had a small unicef logo for years but it brought a lot of attention to us, and I know it was pretty special because it was a free sponsorship space, very unique.
The Bitcoin logo on Watford sleeve was also really cool, so small, so noticeable, and it wasn't even Sportsbet but I think everyone who asked or wondered found out it was because Sportsbet was a crypto accepting place.
Arsenal sponsorship seems different though, it's like just a betting partner, if I'm not mistaken. But to see those Gunners on the website, truly special.