Hello all, first time poster and very formal.
The title is as accurate as it is long.
Alternative racial favored class bonuses applies to class features of a given favored class.
Archetypes or alternate class features replaces class features of a class.
So can an alternate class feature 'double' as the class feature it replaces with respect to alternative racial favored class bonuses?
That is of course if there are mechanics to allow such a substitution, for example that a class feature is replaced by an alternate class feature with a similar numerical progression.
Example: Human barbarian level 6 with the superstitious archetype.
Normally this class would be able to "add a +1/2 bonus to trap sense". But since this class feature is replaced by mechanically similar Sixth Sense alternate class feature. He would instead "add a +1/2 bonus on initiative and a +1/2 insight bonus to AC during surprise rounds". So in this case the barbarian would add +3 to his initiative and +3 to AC during surprise rounds.
I haven't encountered anything that specifically deals with this issue. In the FAQ there is a general question, that might support the above given example, yet it is also somewhat vague:
Rules FAQ wrote:
Archetype: If an archetype replaces a class ability with a more specific version of that ability (or one that works similarly to the replaced ability), does the archetype's ability count as the original ability for the purpose of rules that improve the original ability?
It depends on how the archetype's ability is worded. If the archetype ability says it works like the standard ability, it counts as that ability. If the archetype's ability requires you to make a specific choice for the standard ability, it counts as that ability. Otherwise, the archetype ability doesn't count as the standard ability. (It doesn't matter if the archetype's ability name is different than the standard class ability it is replacing; it is the description and game mechanics of the archetype ability that matter.)
Relevant links:
Barbarian alternative favored class bonuses
Barbarian Superstitious Archetype