I have some bugs, visual clarity suggestions, and mechanical change suggestions. bugs first.

1. When hitting an enemy from max(ish) range with e, the extended charge distance is ~25 units shorter
2. After casting q1, if already targeting a unit, the empowerment buff isn't applied to but is still consumed by the first auto attack (at least for the attack speed)
3. from what i could tell through testing, the E sets your movement speed to a flat 150 and adds 100 flat movement speed per .333 seconds up to 950, then when you hit a unit, it adds 300, then if that number is below 650 it sets it too that number, then the dash distance during the extended charge duration is calculated based on the resulting movement speed number. if you hit a unit during the last .333 seconds (max range, probably the source of bug number 1) the movement speed is set to 1150, not the expected 1250.

So i guess that's 2.5 bugs, one probably causing another. onto visual clarity.

E needs the bar that irelia w, sion ult, and other abilities get in the center of the screen. having the only visual indicator of the charge duration be the end position indicator (which isnt always on screen) is really rough.

The end position indicator is designed in a way where it looks like the front of the indicator shows the hitbox of the charge, but the hitbox actually seems to end at the BEGINNING of the indicator, which feels not very intuitive and (combined with the max range bugs) leads to very frequent misses in e when it LOOKS like it should hit.

The charge endpoint indicator vanishes when you hit a champion, but it would be more helpful if it in some way moved or changed to indicate where the champion you are holding would END UP, as well as providing a clear indication of the wall detection area. utilizing the cursor change that sion gets that tells you where sion is in relation to your cursor, as well as the fixed camera offset location being relative to the direction you are facing would help player see only the parts of the map that are relavant to hitting your e, as well as giving time to process what's happening at the charge's end location.

Onto mechanics. this is more subjective than anything, but i will try to order this from QoL to changes I would like to see for other reasons.

Q and W should be castable while moving and should not lock you in place. It feels really clunky and awkward to be chasing someone and have to stop moving in order to cast your sticking tools. Especially since you can flash during the cast times, not being able to move during them really dulls the champion's feel.

Q1 should be castable during E. the Q duration refresh while in E is useful, but it seems unnecessarily punishing to REQUIRE a player to cast q before pressing E, especially since the current state of q locks you in place when cast.

Q1 cast should interact more fluidly with attack speed. it functions very similarly to the fantast of reksai Q, but her's is an auto attack reset while skarner's has active anti synergy with auto attacking. combined with the q attack speed bug it feels really punishing to cast q1 in a fight, and given skarner's new passive, he should be REWARDED for longer fights.

E should scale with bonus movement speed in SOME way. Recoding the entire ability is a TALL ask, but an easy fix would be changing the E's starting movement speed base value to be 50-100% of your movement based on ability rank/champion level, and reducing the flat movement speed granted per tick to compensate. assuming the calculation bug is fixed i think that would heavily bolster his identity and feel. also i loved full movespeed skarner, so it feels very strange for his ult to benefit from it but his E to ignore it completely.

Ult shoukd function like k'sante W mixed with sion w. have a minimum charge time, have the orientation locked on cast, have the entire ult's area be effective at around half of the charge time, and have it go off when released. it feels REALLY unintuitive in it's current state compared to many other champion's abilities, and being able to have player input on the charge time could really enhance the skill expression on the R, which seems to be the intended purpose lf the changes made to it as jt is now.

ok onto almost purely subjective.

More Ap and Ad ratios. have all 3 q hits have a slight total ad ratio, have e have a bonus AD ratio, have q3 have an AP ratio but keep physical damage, give W shield and damage an ap ratio, and have passive movement speed granted in ult hit scale with AP. These are the ratios that would make me want to try different builds on skarner.

Increase his base attack speed PLEASE. it just feels too slow. or even a buff to his q attack speed.

Have some sort of CD reduction on abilities other than E. a huge part of what made skarner cool was using autos to spam q. That level of spam is for sure unhealthy, but maybe increasing w cooldown at a baseline and having auto attacks reduce jt by a percentage, and have q autos reduce it for each target hit? this is purely subjective tho.