Matthew 20:26

Οὐχ οὕτω δὲ ἔσται ἐν ὑμῖν· ἀλλ᾽ ὃς ἐὰν θέλῃ ἐν ὑμῖν μέγας γενέσθαι ἔσται ὑμῶν διάκονος·

RBT Translation:

διάκονος - Functional Agency of Yourself

It will not be in this way within yourselves but rather, whoever might desire to become a mega one within yourselves, he will be an agent of yourselves.

διάκονος

the functional agent, auxiliary, go-between, instrument, surrogate.

The διάκονος acts not for their own selves, but in place of the one who sends them.

Tychicus and Phoebe serve as the Small One's ("Paul") stand-ins—delivering letters, encouraging churches, conveying teaching (Eph 6:21; Rom 16:1). He is the small one who is present, "in spirit."

Julia Smith Literal 1876 Translation:
But it shall not be so among you; but whoever should wish to be great among you, let him be your attendant;

LITV Translation:
But it will not be so among you. But whoever desires to become great among you, let him be your servant.