OET interlinear 2 YHN (2 JHN) 1:7

uW Translation Notes:

Note 1 topic: grammar-connect-logic-result

ὅτι

(Some words not found in SR-GNT: Ὅτι πολλοί πλάνοι ἐξῆλθον εἰς τόν κόσμον οἱ μή ὁμολογοῦντες Ἰησοῦν Χριστόν ἐρχόμενον ἐν σαρκί Οὗτος ἐστίν ὁ πλάνος καί ὁ ἀντίχριστος)

The word For introduces the reason why John wrote about the commandment to love and obey God in the previous verses—it is because there are many who pretend to be believers but they do not love or obey God. Use a natural way to introduce this reason in your language. See the UST.

Note 2 topic: figures-of-speech / explicit

ὅτι πολλοὶ πλάνοι ἐξῆλθαν εἰς τὸν κόσμον

(Some words not found in SR-GNT: Ὅτι πολλοί πλάνοι ἐξῆλθον εἰς τόν κόσμον οἱ μή ὁμολογοῦντες Ἰησοῦν Χριστόν ἐρχόμενον ἐν σαρκί Οὗτος ἐστίν ὁ πλάνος καί ὁ ἀντίχριστος)

The phrase gone out into the world describes the way that the false teachers traveled around, as John discusses in 1:10–11. You could include this information if that would be helpful to your readers. Alternate translation: [For many deceivers are going around from place to place]

Note 3 topic: figures-of-speech / metonymy

Ἰησοῦν Χριστὸν ἐρχόμενον ἐν σαρκί

Jesus (Some words not found in SR-GNT: Ὅτι πολλοί πλάνοι ἐξῆλθον εἰς τόν κόσμον οἱ μή ὁμολογοῦντες Ἰησοῦν Χριστόν ἐρχόμενον ἐν σαρκί Οὗτος ἐστίν ὁ πλάνος καί ὁ ἀντίχριστος)

The expression coming in flesh is a metonym for being a real, physical person and not a spiritual being only. Alternate translation: [that Jesus Christ came as a real human]

Note 4 topic: figures-of-speech / explicit

οὗτός ἐστιν ὁ πλάνος καὶ ὁ ἀντίχριστος

(Some words not found in SR-GNT: Ὅτι πολλοί πλάνοι ἐξῆλθον εἰς τόν κόσμον οἱ μή ὁμολογοῦντες Ἰησοῦν Χριστόν ἐρχόμενον ἐν σαρκί Οὗτος ἐστίν ὁ πλάνος καί ὁ ἀντίχριστος)

This refers back to the situation of people teaching falsely that Jesus did not have a body of flesh. John is saying that people deceive others in this way because the original deceiver (the devil) directs them to do so. You could include this information if that would be helpful to your readers. Alternate translation: [This is the work of the deceiver, the antichrist] or [This kind of teaching comes from the one who is the deceiver and the antichrist]

Note 5 topic: figures-of-speech / doublet

ὁ πλάνος καὶ ὁ ἀντίχριστος

the deceiver the (Some words not found in SR-GNT: Ὅτι πολλοί πλάνοι ἐξῆλθον εἰς τόν κόσμον οἱ μή ὁμολογοῦντες Ἰησοῦν Χριστόν ἐρχόμενον ἐν σαρκί Οὗτος ἐστίν ὁ πλάνος καί ὁ ἀντίχριστος)

The terms deceiver and antichrist refer to the same person (the devil). It may be helpful to clarify that in your translation. Alternate translation: [the deceiver, that is, the antichrist]