They do. Hasbro has a license to produce Trek toys from TOS to Star Trek XII.Good idea with the two-packs!
TOS Kirk and Gorn
TOS Kirk and Khan
Movie Kirk and Khan
Picard and Q
Sisko and Dukat
Janeway and Borg Queen
Archer and Silik
nuKirk and Nero
The list would go on and on and on....
I'm not sure that Hasbro actually has the rights to Prime Trek.
Like they do with Star Wars, Hasbro isn't the only company to produce toys from a particular licensed property. In some instances, a big company like Hasbro can hold the master toy license and then sub-license out to other smaller companies for specific products.DST currently has the license for trek in the prime timeline. In fact they are already working on a Trek Select line with TOS characters with elaborate/detailed backgrounds. The first two are Spock with the Horta from "Devil in the Dark" and a Kirk and Kahn in Engineering from "Space Seed."
Plus DST has done plenty of two packs of characters from TOS/TOS Movies/TNG.