So I have restarted my Skyrim save since my old one is too glitched up from past mods I removed. Now I am at the part where Alduin is suppose to summon the dragon while you and Delphine hide behind a boulder. But the problem is, Alduin is not there at all. Its just the Dragon Soul Absorb effect going on above the sealed burial. I dont know what to do. I considered skipping the quest with console commands but Im not so confident since it may occur at some point again. Anyone got a clue how to fix this?

Same thing happened to me. Only thing that I could do was use the console.

Are there side effects in the future quests?

Honestly I'm not sure. But I remember not being able to absorb dragon souls. Had to go back to the place and wala he was there but I couldn't hit him had to disable him via console and that fixed the issue with the dragon souls. I never did the next quest afterwards after that happened so not sure.

Thanks, I will keep going with the console way I guess...