According to https://issuetracker.unity3d.com/issues/lens-flare-not-working-in-hdrp-preset-project, the simple lens flares won't work due to it being deprecated. https://github.com/Unity-Technologies/PostProcessing/issues/354 asks for the old lens flares image effect to be brought into the new Post Processing stack, but as of right now, there's been no updates about it. Googling doesn't seem to give me many answers either.
If we're using HDRP, what are we supposed to...
What are we supposed to use for lens flares?
If we're using HDRP, what are we supposed to...
What are we supposed to use for lens flares?