Similar machines

Ferguson Big Board

The Furguson Big Board (FBB) was a computer board designed for hobbyists. The FBB was a direct progenitor of the Kaypro II mainboard. Kaypro did not license this design but based on the schematics and layout of both boards it is clear. See RetroCMP for further details

Osbourne

Osbourne 1

The Osborne 1 shipped in July 1981. It appears that Non-Linear Systems was already developing the Kaypro II by this point but it is certain that the Osborne 1 influenced the final version version of NLS's machine.
The weaknesses of the Osbourne 1 was it's 5 inch screen and single density floppy drives.

Osbourne Executive

The Executive was a upgraded Osbourne 1 that improved the Osbourne line to be more competitive with the Kaypro by increasing the screen from 5 to 7 inches (the Kaypro was a 9 inch screen) and double density floppy drives. It was introduced in April of 1983.
Osbourne filed for bankruptcy in September of 1983.

Xerox 820

The Xerox licensed the Furguson Big Board design for the mainboard of the 820.

Zorba

"The Zorba is a portable microcomputer designed to compete with the likes of the Osborne 1 and the Kaypro II."
InfoWorld June 6, 1983

Otrona

The Otrona Attaché released in April 1982 it is a CPM machine with a Z80 processor. Otrona also developed the 2001 in May 1984 which was an 8088 machine but like the Kaypro 16 was not truly IBM compatible. The company filed for bankruptcy in September of 1984.