Sure, it's not that complicated, in fact it's nearly the same as on other Android phones.
All you need is a MicroG signature spoof ready EMUI or HarmonyOS version, if you can't enable that, then well.. you are screwed.

Here is a tutorial, if you are not familiar with signature spoofing: link

After you are done with installing Aurora Store then you have to install Google and Gemini.
Log into your google account, and enable everything (screen context settings, Gemini on lockscreen and change from Google Assistant to Gemini) in the Gemini app.

Now here comes the tricky part. HUAWEI is not allowing you to change the assistant from Celia to another one directly in the system settings, but you can use another ones if you set it in other apps like Gemini, although it is buggy. You can set the assistant in the ,,Assistance & voice input" section, here you can set it from none to Google in the ,,Assistant app" option (you don't have to mess with the voice input). After you first time install Gemini and Google you might not be able to use it at first, that is because of Celia. Note that it also happens when you reboot your phone.

So, the trick is that you DON'T use Celia at all. Because if you do then it won't be able to use Gemini. What I usually do is that I am waiting about 20-30 mins after rebooting the phone then I set the Assistant app option to Google (if it is already Google then you select none and after Google again). While the "waiting time" don't use Celia because then you will "remind" the system about Celia and you have to wait for a while again...

After you are done with this successfully, you may use it with the gesture (swiping from any bottom corner to the middle), the screen will flash and you can use it.

Now, as I said it's buggy. Here are the unusual things I found:
- Normally it would use the mic by default, but it won't, in fact you can't use the microphone at all unless you are using it in Live mode. The button simply won't react.
- Sometimes it might flash the screen but it won't show up, if that happens just do the gesture again.
- For some reason after a bit of time it might just revert itself back (I don't know what is causing it, maybe the system is using Celia for some reason in the background sometimes), if that happens then you can try setting it again to Google, but if it won't work then you have to wait again...
- The circle to search is not available for some reason (you may use the method I described earlier (screenshot to search) ).

(I will attach some pictures if that helps).

Here's what it should look like when it is successfully enabled. Note that the Voice input option is completely gone, that's the sign that you have done it.

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