Indeed Hussain is one of the Asbat.

[Soccer]

"God loves Hussain and loves who loves Hussain, indeed Hussain is from the asbat".

The phrase, "Hussain is one the of the asbat" is seen to imply two facts:

"Hussain being from the Asbat implies God loves him"
"Hussain being from the Asbat implies God loves who loves Hussain"

Both these phrases would not be true if it just meant tribe, as that would almost be meaningless in this regard, nor the tribes from the Prophet (s) offspring, as that would be meaningless as well. 

A better translation would go to the original meaning, which is branches. Tribes can metaphorical be said to be branches linking to a root branch, but the original meaning doesn't have to be tribes.

Indeed, this can be one way the Prophet (s) is interpreting what is meant by Asbat in Quran.

Asbat in Quran

Asbat is brought in context of Ibrahim, Ismail, Isaac, Yaqoub in the 2nd Chapter.  Tribes doesn't seem to have much meaning, but the meaning of Ismail, Isaac, and Yaqoub being branches of the Ibrahim and there being more like Yusuf, is more in line with that,

Like wise, in Suratal A'raaf, the flow that it refers to the course from Moses' people that guided by the truth and they were split into themselves twelve courses as branches, makes more sense in light of that.  This would the successors of Moses were Twelve and they were together one course to God and yet split to twelve courses as branches.

What is interesting is there is a word that refers to water splitting and is similar in this respect in Hebrew, and the Quran by linking this issue with the twelve springs can be saying a lot of verses got misinterpreted in Hebrew to be about tribes while it was really about the successors being like springs of water going back to one root and split from one water. In this regard the miracle of Moses would show even twelve springs is possible in this regard and not impossible to as a parable safeguard the meaning of the word.

In light of this the word Asbat is holy in Quran and refers to those who are branches linking back to a founder,  Hussain (a) thus being of one of the Asbat,  implying that God loves those who love him,  would be due to this being a holy position chosen by God as a means to approaching God.

While again, tribes, would not imply any of this, and be meaningless to us as guidance in both Quran and Sunnah.