So called 'Royal We' in the Quran
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3875 He said, "O Satan, what prevented you from submitting to what I have created by My hands? Are you too arrogant? Or are you one of those exalted?"
711 We created you, We shaped you, and then We said to the angels "Submit to Adam;" so they submitted except for Satan, he was not of those who submitted.
238 We said, "Descend from it all of you, so when the guidance comes from Me, then whoever follows My guidance, they will have nothing to fear, nor will they grieve."
I humbly believe that the above verses make it clear that the god refers to Itself in the first person singular and the first person plural. The following verses indicate that the god also speaks of Itself in the third person singular
223 If you are in doubt as to what We have sent down to Our servant, then bring a chapter like this, and call upon your witnesses other than God if you are truthful.
2455 God promises those among you who acknowledge and do good works, that He will make them successors on earth, as He made successors of those before them, He will enable for them their system which He has approved for them, and He will substitute security for them in place of fear, that they serve Me and do not associate anything with Me. As for those who reject after that, they are the transgressors.
Perhaps Arabic doesn't really have a royal we in it, but does that matter? The Arabic of the great reading is said to defy the rules of Arabic grammar anyway as it's an informal form of Arabic and not Classical Arabic.