Paul uses fruit as a metaphor for what people can see in other people. AT: “people whom the Spirit controls will display love … self-control like a tree produces fruit” (See: rc://en/ta/man/translate/figs-metaphor)
“Fruit” here is a metaphor for “result” or “outcome.” AT: “what the Spirit produces” (See: rc://en/ta/man/translate/figs-metaphor).
Paul speaks of Christians who refuse to live according to their sinful nature as if it were a person and they have killed it on a cross. AT: “refuse to live according the sinful nature with its passions and desires, as if they killed it on a cross” (See: rc://en/ta/man/translate/figs-personification and rc://en/ta/man/translate/figs-metaphor)
The sinful nature is spoken of as if it were a person that had passions and desires. AT: “their sinful nature, and the things they strongly want to do because of it” (See: rc://en/ta/man/translate/figs-personification)