How to set severityOverrides in lintOptions?

I would like to share what I'm doing.

Instead of set severityOverrides, you can call one method to each type of flag that you want to set.

lintOptions {
    ignore "RtlEnabled", "RtlHardcoded", "RtlSymmetry" ....
    warning "RtlEnabled", "RtlHardcoded", "RtlSymmetry" ....
    error "RtlEnabled", "RtlHardcoded", "RtlSymmetry" ....
    fatal "RtlEnabled", "RtlHardcoded", "RtlSymmetry" ....
    informational "RtlEnabled", "RtlHardcoded", "RtlSymmetry" ....
}

In your case, you can do:

lintOptions {
    warning "MissingTranslation"
}

I'm not sure if you can manually set severityOverrides since it is a read only property.

So, I think you really must call one of the methods above (error, fatal etc..) to override the property that you want

(Not an answer-answer, but this is what I used as an equivalent replacement when I couldn't get lintOptions.severityOverrides to work)

Drop a lint.xml file with the same configuration at the root of the module.

<?xml version="1.0" encoding="UTF-8" ?>
<lint>
    <issue id="MissingTranslation" severity="warning" />
</lint>

You also get a richer API to tune lint warnings through lint.xml.