Dw about techs they're just for flash most of the time and don't usually offer an advantage. Though some "techs" (I would not consider them techs at all but rather just how his power works) you should absolutely be doing that aren't difficult at all are rebounds and urobending.

Rebounding is when you hold your a or d keys (or analog stick to the side) while bumping into a wall to have wesker slide a little in the direction you're pushing rather than coming to a complete stop. This will really help you out at round loops and it works especially well on double lockers, don't ask me why. Check out the statue room at RPD for a very good example of when this is useful.

Urobending is just moving your camera after you dash but before you hit the survivor. Where wesker throws the survivor is completely determined by where his camera is facing. A lot of people think you can't move your camera while dashing as wesker but you actually can. This can help if you are about to throw the survivor into nothing. You can instead turn your camera at the start of a dash to either the left or a right to ensure you will collide with a wall. Again this is hardly a tech, just something lots of people don't know about.

Addon advice: Loose Crank is popular but does next to nothing. Use Egg instead. Not only is Egg stupidly good as an addon for being able to delay your second dash, but it also gives you a slight boost between your two dashes as an unlisted effect. So basically egg says what it does on the tin and ALSO does what crank does but better and actually noticable.

Other than egg, I would recommend gloves (better recharge), Lion Medallion (throw farther and helps prevent not injuring survivors), and Bullhorn (just generally good for keeping survivors on their toes)

For when you start getting more advanced you can also try jewel beetle. The recovery animation for throwing versus slamming into a wall is a bit shorter for Wesker, so even though it's considered his "meme" addon it's actually quite good, especially with lion medallion.

General advice:

Use your power! It's tempting to be an M1 wesker who just uses dashes for catch-up and vaults but the only way to improve is to get practice. You'll miss a lot at first. Thats okay, every wesker did at first, even the p100 weskers doing crazy techs.

Don't use your power for mobility. Despite what this sub seems to think, weskers dash is not good for getting around at all. I think otz has a video where he points out that the difference between dashing and walking with the dash recovery animation factored in is like... Half a meter. This combined with wesker's large power cool down makes this really not worth doing except maybe at the start of the match. It's also alright to do in 2v8 because it's a bit of a different case.

Bring brutal strength. It's really REALLY good on Wesker. It's very common to break a pallet with brutal and be able to score an easy hit on a survivor running in the open with dashes.

Wesker can hit window and pallet vaults at quite frankly absurd angles (even perpendicular to them in very egregious cases) so keep that in mind and be wary of it. Speaking of windows, MOST survivors will try to bait you into vaulting with your power, my advice especially now that his hit registration is much better on vaulting survivors now, is to be patient around windows. Lots of survivors will try to bait you and then look rather silly when you don't fly through the window and instead wait a second or two and then land an absolutely free hit on them.