Here are links to Keyboards and Fonts used to write Ethiopian languages. You can read more on Ethiopic / Saba script here.

Keyman Keyboards for Ethiopian languages

Ethiopic / Saba script:

• SIL Ethiopic
• SIL Ethiopic Power-G

Latin script:

• SIL Ethiopian Latin

Fonts

Fonts supporting Ethiopic / Saba script:

• Abyssinica SIL

Fonts supporting Ethiopian Latin scripts:

• Doulos SIL
• Charis SIL
• Andika