At the beginning of Avengers: Endgame, in what order did Thanos destroy the Infinity Stones? What Stone would he destroy last?
Or could he use two Stones at the same time and have them destroy one another?
The Avengers track Thanos down by the energy signature emitted by the destruction of the stones, which is described as similar or comparable to the one emitted during the snap. Additionally, we see that the act was powerful enough to damage Thanos, whereas the snap left the (admittedly armored) Thanos whole.
From this, I think it's a safe assumption that destroying the stones required the combined power of all stones at once, similar to the expenditure of energy required for the snap, and perhaps even more so.
I saw no indication or reason to believe they were destroyed individually.