Warhammer: Age of Reckoning comes to mind.
Certain races (and classes) were 'gender locked'. Wildstar as well. If we wanna point to an FF Franchise, 11 comes out with genderlocked races.
Tera online and BnS are more recent examples that have this.
If you go beyond the scope of just MMOs and focus on online games with multiplayer and RPG elements, Diablo II also had things locked. Though the nuance there was that race/class was somewhat interchangeable as terms colloquially. Maplestory kinda falls into this as well as there are 'different races' (though by appearance they are all human more or less), did genderlock some of their classes/races.
Point stands that the concept of "Genderlocked" has been around for a while and been understood for what it is. If we want to talk about expanding it to be more specific or change the understanding (Such as saying "Genderlocked Races" or "Genderlocked Classes") that can be debated and discussed.
But again, the issue here is that the OP and similar detractors are arguing over the semantics of a word rather than the core issue which is the word is generally understood and associated with. We want to discuss how to use genderlock, start a thread for it. Dont say 'genderlock' is the wrong word to use and because of that we should be totally happy the devs made two races that are limited to a single sex. It's funny cause it's clearly understood by the OP and similar that the point being made is about Hrothgar being male and Viera being female is the core of the issue. They DO understand the common use of the term. It's strange that they would then argue that the term is being used wrong and then suggest that we should be happy with what we have, completely ignoring the core of the grievance in the process because the terminology being used that they clearly understand the meaning of is not semantically correct for their tastes.