Migrating to WonderPush is easy: all you have to do is add WonderPush to your website.
Users that visit your site will be reachable with WonderPush and the others with OneSignal so you can push on both services until enough users have migrated to WonderPush.
This guide will help you remove OneSignal from your website and add WonderPush.
WonderPush and OneSignal SDKs expect different push notification formats, so importing your push tokens into WonderPush is not recommended. Instead, just let users visit the new version of your website and automatically migrate to WonderPush.
Remove the OneSignal SDK initialization code that you added when you followed OneSignal's setup guide.
OneSignal.push) or replace it with its WonderPush equivalent (see our Website SDK reference).
Follow our Website Quickstart guide to add WonderPush to your website.
Once you've got WonderPush on your website, users that visit your site and have already granted the push notification permission will automatically appear in your WonderPush dashboard.