When you target a gear with Adaptatron, do you have to pay Deflect if unit has it even via the gear? Svellsongur is attached to Ornn?

No, you do not have to pay the Deflect cost when targeting an attached piece of gear, even if the unit it is attached to has Deflect.

According to RiftJudge FAQ #734:

• "Equipment cards have their own properties, not those of the unit they are attached to (the Top Most Card)."
• "If a spell or ability targets an equipment that is attached to a unit with deflect, does the deflect need to be paid? Ruling: No, you can target attached equipment normally."

Why this is the case:

1. Deflect applies to the unit, not the gear: Deflect is a keyword that grants protection to the permanent that has it. When Svellsongur is attached to Ornn, Forge God, the Deflect keyword is active on Ornn. It does not transfer to the Svellsongur card itself.
2. Gear properties are distinct: Even while attached, the gear remains a separate game object from the unit. Targeting the gear is not the same as targeting the unit, so the unit's Deflect protection does not trigger.
3. Inactive text: As noted in FAQ #5734, while gear is attached, its own rules text becomes inactive. Even if the gear were to somehow gain Deflect while attached, that text would be inactive and would not provide protection.

Therefore, when you use Adaptatron to target an opponent's attached gear (like Svellsongur attached to Ornn), you are targeting the gear, not the unit, and the Deflect cost does not apply.