Regarding weaknesses, this is where things get complicated for Zion Tupuola-Fetui, starting with the fact that he seems to not have more than 2 different speeds in his playstyle, especially when it comes to changing pace in pass rush situations. Zion is either all in or jogging; there's literally nothing in between. Either 100% or 50%. In my opinion, he would benefit greatly from varying his running pace, especially considering his good explosiveness. Using his strong initial explosiveness to put the blocker under stress, then slowing down to 60-70% to execute a clean move, and finally re-accelerating in a highly explosive manner at the end of the move could elevate him to a whole new level as a pass rusher. This is even more pertinent considering he seemed to have this quality during the 2020 season (his most accomplished in College Football).
I am also quite eager to see his results at the combine or Washington's Pro Day during the agility drills, as I think there's a risk of Zion not posting good times due to this issue.

As you've gathered, I have doubts not only about his level change but also about his direction changes in play, especially regarding his overall agility, which I find to be quite average. As we've just seen, Zion is unable to manage his speed; he is either stationary or in full sprint. If that's already an issue, we must also add the fact that he is often "straight as an I" when he plays or moves. Zion is constantly too upright; he plays too high, runs too high, and moves too high. And if there's one thing I've never stopped hearing during drills that help work on direction changes, regardless of the position concerned, it's to stay low and play on one's center of gravity and step frequency. For Zion, it's the complete opposite, and that's how we end up with absolutely shameful plays like when he was humiliated by Caleb Williams with 3:10 remaining in the 3rd quarter of the game against USC.

Previously, in the strengths section, we discussed ZTF's good game reading, which ultimately was too seldom visible due to a weakness that directly impacted it. Now, we're addressing that issue. Zion is far too disengaged in run defense, and that's putting it mildly. Because, for one, he has shown several times this season that he has absolutely no interest in defending the run. He was both uninvolved and unwilling to get into the fray. For me, this kind of attitude is clearly a red flag for a defensive line player. I believe this is partly why ZTF wasn't used much this season. I don't have his exact snap count, but compared to his teammate Bralen Trice, whom I've also scouted and who plays the same position, the difference is significant.

Since Zion was unwilling to exert himself in run defense, his good reading of the game most often went to waste.

Regarding pass rush, something that particularly frustrated me with Zion is that he tries far too often, much too often, to jump the snap. (A player is said to "jump the snap" when they try to move just before the snap, guessing the quarterback's count, thus allowing them to be in motion before the blocker and thereby gain a direct advantage over them. For those lucky enough to have seen it, the former Seattle Seahawks safety Kam Chancellor executed it perfectly against the Rams in a now-legendary play. For the older generation, former Steelers safety Troy Polamalu was also very fond of snap jumping when sent on a blitz).
Zion was quite lucky not to get called out more often by referees this season because, although this tactic could have been a strength if it were well-mastered, it's clear that it's not the case. Zion is often out of position or poorly placed at the moment of the snap. Moreover, this is exactly the kind of thing veteran quarterbacks love to exploit to trap rookies, and I'm concerned that ZTF might cost his team some flags during his career if his coaches don't quickly make him understand that it's a problem.

Still on the topic of pass rush, and revisiting a point briefly mentioned in the strengths section, Zion's ability to bend is very average. Furthermore, he makes the task even harder for himself since his pad level is too high, as we've observed earlier. If we add to this the fact that Zion isn't strong enough in his stances and that he also struggles significantly to resist the push from offensive linemen, largely due to playing too high, it quickly becomes clear that this is a complicated issue.
I don't know if Zion will be able to improve on his ability to Bend but when we see that he lacks significant power and does not dominate despite all his years spent in college football, it quickly becomes apparent that this is a key area for development if he wants to survive in the NFL as a pass rush specialist. Moreover, if Zion could lower his center of gravity by forcing himself to play lower, he could not only try to compensate for his lack of lower body strength but also see an improvement in his agility.

Finally, the last two points that really drive the nail into the coffin of ZTF's value are his Injury concernsand the fact that he will be 24 years old in his rookie season, it's difficult to see him as a riser among franchises. On the contrary, I think that just because of this, without even taking into account the player's profile, his strengths, his weaknesses, or anything else, he is likely to fall in the draft.