Is. 9:6 may be honestly translated in several ways.
The Leeser Bible also translates it:
“Wonderful, counsellor
of the mighty God,
of the everlasting Father, the prince of peace”
Also,
An American Translation (by trinitarians Smith and Goodspeed) says:
"Wonderful counselor
is God almighty, Father forever, Prince of peace."
From the Is. 9:6 footnote in the trinity-supporting
NET Bible:
".... some have suggested that one to three of the titles that follow ['called']
refer to God, not the king. For example, the traditional punctuation of the Hebrew text suggests the translation, 'and the Extraordinary Strategist, the Mighty God calls his name, "Everlasting Father, Prince of Peace."'"
And,
‘Wonderful in counsel
is God the mighty, the Everlasting Father, the Ruler of Peace’ (Hertz 1968).
Of course it could also be honestly translated: "Wonderful Counselor and Mighty God
is the Eternal Father
of the Prince of Peace."
And the
Tanakh by the JPS, 1985, translates it:
[1] “The Mighty God is planning grace;
[2] The Eternal Father [is] a peaceable ruler.”
This latter translation seems particularly appropriate since it is in the form of a parallelism. Not only was the previous symbolic personal name introduced by Isaiah at Is. 8:1 a parallelism (“Maher-Shalal-Hash-Baz” means [a]“quick to the plunder; swift to the spoil” -
NIV footnote) but the very introduction to this Messianic name at Is. 9:6 is itself a parallelism: [a]“For unto us a child is born; unto us a son is given.” It would, therefore, be appropriate to find that this name, too, was in the form of a parallelism as translated by the Tanakh above.
So it is clear, even to a few trinitarian scholars who dare admit it, that Is. 9:6 does not necessarily imply that Jesus is Jehovah God.
For an honest personal study concerning this see:
Isa. 9:6 "Mighty God, Eternal Father"