最简单的解决方案:

iOS 10及以上版本，Swift:

button.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.titleLabel?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
button.imageView?.transform = CGAffineTransform(scaleX: -1.0, y: 1.0)

在iOS 10之前，Swift/Obj-C:

button.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.titleLabel.transform = CGAffineTransformMakeScale(-1.0, 1.0);
button.imageView.transform = CGAffineTransformMakeScale(-1.0, 1.0);

iOS 9及以上版本，Swift:(推荐)

button.semanticContentAttribute = .forceRightToLeft

子类化和覆盖layoutSubviews可能是你最好的方法。

引用自:iPhone UIButton -图像位置

当标题发生变化时，只需更新插图即可。你需要在另一侧用等量的、相反的插页来补偿插页。

[thebutton setTitle:title forState:UIControlStateNormal];
thebutton.titleEdgeInsets = UIEdgeInsetsMake(0, -thebutton.imageView.frame.size.width, 0, thebutton.imageView.frame.size.width);
thebutton.imageEdgeInsets = UIEdgeInsetsMake(0, thebutton.titleLabel.frame.size.width, 0, -thebutton.titleLabel.frame.size.width);

Swift 4 & 5

改变UIButton图像的方向(RTL和LTR)

extension UIButton {
    func changeDirection(){
       isArabic ? (self.contentHorizontalAlignment = .right) : (self.contentHorizontalAlignment = .left)
        // left-right margin 
        self.imageEdgeInsets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
        self.titleEdgeInsets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
    }
}

iOS 15带来了一个更新，现在你可以用一种更简单而不混乱的方式来处理按钮中的图像放置。没有insets。

在XIB /故事板: 简单地设置按钮的“位置”属性为领先/训练/顶部/底部后，添加一个图像属性按钮。由于它是领导/培训，所以它支持RTL有一个额外的优势

**在代码中(编程方式):** 以编程方式使用“按钮配置”属性

这不是一个向后兼容的功能，只能在iOS15+中工作，正如WWDC '21 - https://developer.apple.com/videos/play/wwdc2021/10064/?time=236所演示的那样

开发人员文档:https://developer.apple.com/documentation/uikit/uibutton/configuration?changes=_4

一个快速的选项，做什么你想要不玩任何插图:

class RightImageButton: UIButton {

    override func layoutSubviews() {
        super.layoutSubviews()

        if let  textSize = titleLabel?.intrinsicContentSize(),
                imageSize = imageView?.intrinsicContentSize() {
            let wholeWidth = textSize.width + K.textImageGap + imageSize.width
            titleLabel?.frame = CGRect(
                x: round(bounds.width/2 - wholeWidth/2),
                y: 0,
                width: ceil(textSize.width),
                height: bounds.height)
            imageView?.frame = CGRect(
                x: round(bounds.width/2 + wholeWidth/2 - imageSize.width),
                y: RoundRetina(bounds.height/2 - imageSize.height/2),
                width: imageSize.width,
                height: imageSize.height)
        }
    }

    struct K {
        static let textImageGap: CGFloat = 5
    }

}