Other mistake: When Phoebe gets the premonition to see all the loss, she sees the scene where Piper dies in All Hell Breaks Loose. Since time was rewound this event never happened in this timeline, and we're never given any reason to believe Phoebe would know this happened after the time reversal.
Other mistake: After they talk to the Angel of Destiny for the first time, they send Leo to ask the Elders if he is legit. After Leo leaves they find out about Agent Jackman, and the following events unfold. After Jackman busts them Piper calls for Leo and tells him "It's OK, you can orb" and he appears asking her "What about Agent Jackman?" Except that Leo was gone before they found out about him and the girls hadn't told Leo yet that he even existed. (00:09:09 - 00:21:58)
Other mistake: When Phoebe is trying to summon Angela the spell doesn't work and Leo says that she needs the power of three. We've seen this spell done with just one sister in the past and it's never explained why they'd need to do it together this time.
Continuity mistake: Whilst Paige and Phoebe are jumping through time, they witness Piper telling Leo she loves him for the first time. After she tells him, Leo orbs Piper and himself away. This doesn't make sense as the first time Leo orbs Piper is in season 2 Episode 8 - the water demon episode - which is actually further on in time from when she tells him she loves him (which is from season 1 episode 21).
Valhalley of the Dolls (1) - S6-E1
Plot hole: Phoebe becomes an empath. But in Primrose Empath (S3:E6) Leo tells the sisters an empath is a mortal who has died and come back as an empath, so it wouldn't be a progression of a witch's powers like it is in this episode. Plus Phoebe isn't dead.
Suggested correction: There is a difference between an Empath and the power of Empathy. A true Empath is a mortal that has died and been reincarnated and they are a separate race of magical beings. But other beings, such as witches, can have the power of empathy. It does get confusing because they refer to a witch with empathy as an empath, but that doesn't mean they are true empaths. In addition, Phoebe developed her empathy powers in her 20's as one of her first powers and her power of empathy is the strongest of any being.
And where is this stated anywhere in the 8 seasons of the show?
Continuity mistake: When Prue is sitting at home bored, she spots the vase with the flowers. In one shot the vase is on the left, and in the next shot it's on the right, then Prue moves it to the left.
Love Hurts - S1-E21
Revealing mistake: After Piper saves Leo, they meet with Phoebe and Daisy downstairs near the living room. Before the darklighter appears, smoke from a fog machine can be seen at the left of the shot to magically transition to the computerized effects. (00:33:45)
Continuity mistake: As soon as the water demon enters Sam, we can see that Prue's hair is completely dry. Then when she flips the switch to electrocute Sam to kill the water demon, her hair goes from dry to wet without ever coming into contact with any water. (00:36:25)
Continuity mistake: In the teaser Piper is reading a fairytale book to her unborn child. When Paige walks in we get a glimpse of the book, and both pages are filled with words. When Paige walks out and we see the book again, the right page of the book has a picture on it. (00:00:15 - 00:01:35)
Continuity mistake: In the scene where Eva is teaching the sisters about ways to draw power on All Hallows Eve, she cuts an apple in half and puts a leaf over the seeds in the center. The leaf goes from small and only covering the center to bigger and covering more of the apple.
Charmed and Dangerous - S4-E13
Character mistake: When Phoebe is describing to Cole the demon she saw in her premonition, she says on the good side of his face he had tribal markings, and Cole says, "Kinda like Belthazar," and Phoebe agrees. Belthazar has no markings like the ones on the demon's face.
Visible crew/equipment: In the scene with Chris and David in the attic, a boom mic dips into the shot. (00:28:50)
The Importance of Being Phoebe - S5-E11
Continuity mistake: When Kaia, pretending to be Phoebe, holds up the document from the bail bondsman, it jumps from her left hand to her right. (00:33:20)
Factual error: Little Piper (from 1975) has blue eyes. She should have brown eyes, like present day Piper.
Revealing mistake: When Phoebe and Paige use Cole as bait to lure Piper to the manor, Phoebe levitates and kicks two furies at once. When they show the front shot of her kicking these two furies, we can see Alyssa Milano's stunt double. (00:34:25)
Continuity mistake: When Devlin uses the Ring of Inspiration on his subordinate, his hand changes orientation from vertical to horizontal. (00:10:35)
Wrestling with Demons - S3-E12
Continuity mistake: When Phoebe finds the lost and found spell for Piper, the paper the spell is written on moves relative to the top of Phoebe's keepsake box. (00:10:30)
Show Ghouls - S7-E15
Continuity mistake: When Phoebe is on the phone with Elise about the Cosmo interview, she jumps between shots from leaning over the kitchen table to sitting straight up. (00:05:45)
Continuity mistake: When Leo hugs Wyatt near the end of the episode, the way the pair hold onto each other changes. (00:38:15)