Not necessarily, but mediation is highly recommended. Why? Because most cases will settle if they mediate. That doesn’t mean that mediation is always required. However, if a party requests the court to order the parties to mediation, courts will order the mediation. So, if you or your spouse wants to mediate, there’s a good chance the court is going to order you to mediate.
In Travis County, there are Local Court Rules that require a mediation before a final hearing if you think the hearing will take longer than 3 hours. At the time I’m writing this, Williamson, Hays and the surrounding counties don’t have a similar rule, but they encourage mediation in situations like this.