If you're looking for something to replace EasyComment, KickoffLabs could be a good option. It's designed for creating and launching viral giveaways, referral programs and product launches, and the service offers bonus entry giveaways, pre-launch waitlists and milestone reward programs. KickoffLabs also can be used in conjunction with other tools like Klaviyo and Mailchimp to help you manage and optimize your campaigns.
Another option worth considering is Loti, which is geared for content protection for public figures. It doesn't offer a direct replacement for EasyComment's giveaway abilities, but it does offer more powerful tools for finding and removing infringing content, which could be useful if you're running a campaign that's also got copyright problems.
If you're looking for a service that's got fraud detection as a top priority, you might want to check out Verisoul. The service automates fraud prevention and detection across a range of signals like device risk and geolocation. That can help keep your campaigns legitimate by blocking fraudulent activity, which could be useful if you want to run a giveaway that's fair and successful.