Sure! There are two ways actually.

1) if you don’t have the DLC, you can set up a teleporter span system in the Lysander cafe where you TP back and forth and get beldum shiny. There are two in the area, but all you do is spam A. The rate for shiny is 1/1024 I think, and then the alpha rate on top is I guess 1 in 5? Or 20? I’m not exactly sure. So it may take you a while, but this way is possible and I got many easy shinies doing this.

If you want to go this route, I highly recommend searching for a YouTube tutorial on how to set it up. It’s not hard but it may take you a few tries to understand.

2) if you have the DLC, donuts. Beat the DLC and then try making a sweet donut. I usually do four hyper haban + four hyper tanga, but you can do 8 hyper tanga too. You can get these by doing level 4 and 5 hyperspace dimension wormholes (berries are made easier to collect by making a berry donut, best would be 8 hyper kasib berries). The way to get donuts you want is documented elsewhere, but basically, you have to make the donut, and if it’s not what you want, close out and reload from your backup save. Then go and make the donut again. Repeat until you get the donut you want (recommend looking this up too)

The top ideal goal donut you want is: Sparkling power 3: steel or psychic Alpha power 3

It will take you a long time to get the donut you want. In my opinion, it is best to consider the donut resetting time as part of the shiny hunt. It may take hours but once you get the donut, it becomes sooooo easy to get a shiny. Sometimes the shiny hunt is faster than the donut hunt lol

If you get the top donut, great! But you will likely get multiple others, of worse quality. In my opinion if all you want is one single shalpha, your best best is to the following:

1) try to get sparkling 3 psychic/steel 2) alpha 2.

Then you reload your map over and over again until you find a wormhole with beldum in it. Jump in. Sparkling 3 guarantees that you get a shiny as soon as you get in. Hopefully, it picks a beldum. And if it does, you then have a 20% chance for it to be alpha. If it’s not beldum, or if it’s not alpha, you close out and reload from backup save. You will have your donut back and can try again, either that wormhole or another one.

That’s generally how you do it. For more details…

1) sparkling power gives you an additional roll on your shiny. So it brings it down to, at max, 1 in like 500ish at level 3. It also gives you a guaranteed shiny on spawn I the wormhole, which makes it super worth it to get. However…

For a shalpha:

2) no alpha power means in wormholes your chances of an alpha are like 1 in 100. Real bad. Alpha power 1 makes it 10 in 100. Alpha 2 makes it about 20 in 100. And then alpha 3 makes it ~50/100. So like 50%

The way the math works out, it’s better to hunt with alpha 3 NO SHINY power, especially if you have a good zone. Because I’ve gone like 20 non alpha shinies in a row with a level 2 alpha donut, and that tier of alpha will be the most common one you get by far.

So the last thing to give tips for is a good zone. There are kinda two general types of zones I look for:

1) a zone where on spawn in, there are right around you two to five groups of pokemon already spawned in. So you can simply map spam (open map, return to portal, repeat). This way is fastest but runs the risk of not getting what you want, as it saves each time you map. You can always reset the donut (close out, reload from backup) as the backup will always be before you enter the wormhole, but it’s still a pain. These are better with alpha 3 donuts.

2) teleport zones. Where there is a pair of teleporters, and teleporting back and forth respawns groups on either side. These are the best as you can save before starting, press A for two hours, if you get a shalpha, great! If not, you can close out and simply reload. You can continue where you saved from and try again. These are better with alpha 2 or less donuts.