To investigate the tomb entrance at the tomb of Alexander the great in Aya: Blade of the Goddess in Assassin’s Creed: Origins interact with the spears on the ground. Interact with the door. Go back down the corridor and hit the cracked wall:
Interact with the cracked wall and squeeze through the open gap.
To investigate the sacred pool in the Temple of Sobek in Krokodilopolis in Sobek’s Tears in Assassin’s Creed: Origins interact with the blood on the rocks on the right side of the enclosure. Interact with the blood on the stairs. Interact with the jar at the bottom of the stairs. Climb up the back wall of the enclosure and the outer wall of the Temple of Sobek. Drop down on the outside and enter the sewers: