This wikiHow teaches you how to upload an image file to Discord from your Android and use it as an emoji in your chats.
Steps

Step 1. Open the Android mobile internet browser
The Discord app doesn't allow you to change server settings or upload an emoji. You will have to enter an internet browser to do so.

Step 2. Go to the Discord website
Type discordapp.com in your browser's search bar and press ↵ Enter or Return on your keyboard.
Alternatively, you can go to discord.gg. This address redirects to the same site

Step 3. Press the ⋮ icon
This button is in the upper right corner of your internet browser. It will open the browser options and a drop-down menu.

Step 4. Click Request Desktop Site from the menu
This will refresh the page and open the desktop version of the Discord website.
- Depending on the internet browser, this option may only be called "Desktop Site".
- If you skip this step and continue on the mobile website, you will not be able to customize the server settings and add the custom emoji.

Step 5. Press the Login button
It's in the upper-right corner of the Discord home page.

Step 6. Login to your Discord account
Enter your email and password, then click on "Login".

Step 7. Choose a server in the bar on the left side
Your chat servers will be listed on the left side of the screen. Find and select the server you want to edit.

Step 8. Press the icon

next to the server name.
The name of the server will be listed in the upper left corner of the page. This button will open a drop-down menu.

Step 9. Click Server Settings in the drop-down menu
This will open the SERVER OVERVIEW menu on a new page.

Step 10. Press the Emoji key in the left menu
Find the settings menu on the left side of the page and choose this option to open the EMOJI SERVER page.

Step 11. Press the Upload Emoji button
This is a blue button on the right side of the EMOJI SERVER page. It will open a list of available charging methods in a pop-up menu.

Step 12. Press Documents or Gallery.
This option will allow you to select and upload an image file from your Android, and use it as an emoji in your chats.
Alternatively, you can select "Camera" and take a new photo

Step 13. Upload the image file you want to use
Browse your files and choose the image file you want to use as an emoji. This will load the selected file.
Once the image file is uploaded, it will be displayed in the emoji list on the EMOJI SERVER page

Step 14. Edit the emoji alias
Press the ALIAS field next to the uploaded image on the EMOJI SERVER page and enter a short alias to use the emoji in your chats.
-
For example, if you set the alias: :example:, write: example: in a chat it will send the emoji to the conversation.

Step 15. Test your new emoji in a chat
Open any chat on this server, type the emoji alias and send it as a message. You should see your new emoji in the conversation.