How they are not like that can be stated clearly. "The wicked are not prosperous" or "The wicked do not prosper" (See: [[rc://en/ta/man/translate/figs-explicit]])
Possible meanings are 1) not standing in the judgment is a metonym for being judged by God and having to leave his presence. AT: "will not continue to stay before God when he judges them" or "will have to leave God's presence when he judges them as guilty" or 2) not standing in the judgment is a metaphor for being condemned in the judgment. "AT: "will be condemned in the judgment" or "will be condemned when God judges them" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Translators can supply the verb "stand." AT: "neither will sinners stand in the assembly of the righteous" or "and sinners will not stand in the assembly of the righteous" (See: [[rc://en/ta/man/translate/figs-ellipsis]])
# nor sinners in the assembly of the righteous
Being accepted by God as righteous is spoken of as standing with the group of righteous people. AT: "and God will not accept sinners along with the righteous people" (See: [[rc://en/ta/man/translate/figs-metonymy]])