A trooper in a fireteam declares Move then BS attack to pitch a repeater near an enemy hacker that has no LoF to the fireteam, therefore is unable to ARO at this point. But if the pitcher is a hacker (like a Barid) or a REM (like a Tsyklon), or if there is a hacker in the fireteam (who activated with it), does the targeted hacker gets an ARO if the BS attack is a success and places him within 8" of the incoming repeater ? The other way round, if I deploy a repeater with an ARO (via a pitcher BS attack or the place deployable skill) and something hackable is in range, do my hackers get an ARO as well against that hackable target that activated inside what is now their expanded hacking area ?
No, due to this part of the Place Deployable Skill: The Token is placed at the Conclusion of the Order in which the Trooper declared this Skill. (See FAQs & Errata. Repositioning is allowed if a Trooper has moved into the chosen position.) The enemy may only react against the Trooper that declares the Skill, not against the Weapon or piece of Equipment that is placed on the table during that Order or ARO. The Repeater/Pitcher doesn't exist until the end of the Order so can't be used by any hackers until the next order. Edit: Also remember that dice aren't rolled until after all skills and AROs are declared, so you won't know if the pitcher has landed or not until after everything has been declared.