LiveRegion.kt

val description = if (checkedState.value) {
    "次へ進むことができます"
} else {
    "次へ進むには利用規約に同意する必要があります"
}

Button(modifier = Modifier
    .semantics {
        liveRegion = LiveRegionMode.Polite
        contentDescription = description
    }
    .fillMaxWidth(),
    enabled = checkedState.value,
    onClick = {}) {
        Text(text = "次へ進む", fontSize = 16.sp)
}