I once found a workaround on a trashpicked Android 5.1 phone by Huawei. There was a shitty third-party keyboard during the setup, so I tapped around and found that it has DLC themes. Attempting to download one resulted in a popup "Offline? Check network settings" with a link into the Settings app, where I could set a lock screen passcode and then remove it, which nullified FRP.
Later, I found a YouTube video with instructions for another exploit, which somehow reached Settings via the screenshot shortcut and then attempting to share it via Gmail. I imagine weird phone brands will have several exploits like this.
I feel like drinking any more water mill make me become a solution