This is false and Eurogamer covered it already. You cannot run both at the same time, but both can be installed. The Valorant anti-cheat just cannot be active (it can be turned off at any time if it is running and requires a reboot before the game can be played if disabled).
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https://www.eurogamer.net/you-cant-play-battlefield-6-and-valorant-at-the-same-time-heres-why