https://github.com/amanharwara/altus/releases
Altus is the very good option to to handle the multiple whatsapp in the system, this is available in appimage format too to run in linux and other platforms.
Altus
Altus is an Electron-based WhatsApp client with themes and multiple account support, available for Windows, Mac and Linux!
Features
Altus uses the GitHub-produced Electron framework to wrap around WhatsApp Web and add extra features to it.
- Multiple Account Support: As of v2.0, you can use multiple WhatsApp accounts simultaneously!
- Native notification support for all of the platforms. Clicking the notification opens that specific chat!
- Online Indicator: Shows an indicator at the bottom-left corner of the chats that are online!
- Dark mode for when you need to chill out your eyes in the night (or even in the day)
- Custom Theme Support: Write your own CSS theme for WhatsApp or use the in-built Theme Customizer to create a new one just by picking colors!
- Available for most desktop platforms including Windows (7 or above), Linux and MacOS.
- Tray icon so you can minimize the app completely and still receive notifications.