If you look at the bullet points on pg 246, only two of 7 make any mention/requirement for two-weapon wielder talent.
Of main pertinence:
"If the character had the Two-Weapon Wielder Talent, he may use Multiple Attacks combat action to attack with both weapons, but each suffers a -20 penalty ..."
Conversely, therefore, if a character does not have the two-weapon wielder talent, his only restriction is he cannot use a Multiple Attacks action to attack with both weapons. He can use a single attack action to attack with both weapons.
Thus, someone without the two-weapon wielder talent can fire Semi-Auto or full-auto with two pistols. That is a Single-attack action. They also get the parry reaction for having a melee weapon in their off hand if they are armed so.
Multiple Attacks action (pg 241) refers to: Swift Attack, Lightning Attack, and the Full Action listed under Two-Weapon Wielder talent (pg 107) (where you can spend a full action to attack with each weapon, basically two-standard attacks, one for each weapon).
Note that nowhere on pg 246 (two-weapon fighting), nor in the entries for semi-auto and full-auto, does it say that wielding two weapons requires the Two-weapon fighting talent. The two-weapon fighting talent just allows you to make multiple attacks with both weapons. So, Two-weapon talent wielders will get 1 additional attack compared to non-two-weapon talent wielders.