Hello there! I hope it’s okay to post guide made by newbie for newbies 
But here it is!
Small guide how to setup plymouth in EOS.
I’m nvidia user and don’t know how do it using amd gpu 
First of all small plan:
- Download plymouth
- Change configs for dracut*
- Enable splash in boot options
- Customize plymouth
- Rebuild initramfs using dracut*
Downloading plymouth
First of all: download.
- Open terminal and run
yay plymouth
- Select package:
if you’re using KDE plasma you can installplymouth-kcm(You will be able to change plymouth settings using GUI)
else installplymouth
Change configs for dracut*
A small clarification: plymouth will work without it, but will appear too late in boot process
- Open terminal and create a new config file for dracut
sudo nano /etc/dracut.conf.d/nvidiaload.conf
- Paste inside file:
force_drivers+=" nvidia nvidia_modeset nvidia_uvm nvidia_drm "
Enabling splash in boot options
To see plymouth we need add quiet splash to kernel parameters
System-md:
- Open terminal and go to kernel parameters
Be carefull! Don’t delete or change something!
sudo nano /etc/kernel/cmdline
- Add
quiet splashafterrw
Nice job we almost done!
Customization!
Plymouth allows you choose and create own themes for boot animations. But in guide I will use theme from AUR.
Non-KDE:
- I hope you don’t close terminal? So we will install our theme! Run:
yay endeavouros
Our theme will be near the end
Install it and then
- Change plymouth config
sudo nano /etc/plymouth/plymouthd.conf
- Insert in config
[Daemon]
Theme=endeavouros
(to list all installed themes: plymouth-set-default-theme -l)
For KDE users:
- Go to the system settings and you will found new menu (if you installed
plymouth-kcm)
(Furthermore you can stop following this guide. It settings is pretty easy and has user-friendly GUI)
Rebuild initramfs*
In this guide I will use dracut, because I’m familiar with it
- Open terminal and run
dracut rebuild
- Reboot
Nice! I hope my guide helps and you actually see boot animation! I decided to make this guide, because I don’t found one in forum (I probably bad searcher) and make it more clear. I will be glad to receive corrections and advice. Have a nice day 