Real Madrid odds are slightly better than Barcelona. Their games in Champions League require more effort from Barcelona's players comparing to Real Madrid's one. Yet everything could happen obviously. I find Barcelona better but sometimes the concentration level is a bit lower which leads to disasters like what happened in Inter's match. Now in the next game vs Inter, it will be bad if Barcelona lose again. After 8 rounds in La Liga, Barcelona received only 1 goal at the opposite of CL where they received 4 in 3 games.
Actually, with all due respect to the opponents in La Liga with whom Barcelona had previously played their matches, it seems that the level of the Champions League teams should be higher in status, and therefore, you should not be surprised at the 4 goals that the team missed in the Champions League. I am rather even more surprised that Barcelona conceded only one goal in La Liga, because the same Celta had a very good chance to score at least one goal in the match in the last round of the championship before El Classico. Xavi is facing a very difficult task right now, because he needs to win against Inter in a Champions League match to keep his chances of reaching the playoffs, and then in four days he will have a game with Real Madrid, where he also needs a result, at least for the sake of prestige. Problems with the squad, taking into account injured players, also contribute little to this. Therefore, taking into account the home status of the match for Real Madrid, the chances of the hosts look more preferable.
Barcelona's defense in La liga is undoubtedly impressive, Real Madrid could have troubles scoring in that game, so i think a draw is most likely to be the result of that match, and with both Barca and Real Madrid attack lately, i don't think we will see a lot of goals too, three goals at max.
It is true that Barcelona's defense is the best this season, which until the 8th round of La Liga, Barcelona only conceded 1 goal. It's a very good record
for Barcelona, and I'm sure the Barcelona defense will try to be consistent. This means that it is not easy for any team to score a goal against Barcelona,
It will be very interesting whether Real Madrid's prolific front line can score a goal against Barcelona. But unfortunately Barcelona's goal productivity
has decreased in recent matches. So hopefully Barcelona's front line can be productive again when facing Real Madrid. El Clasico matches will start in
a few days, but before that Barcelona and Real Madrid will play in the Champions League first, this will certainly be a good warm-up match before
the El Clasico starts. Regarding the prediction of the El Clasico match, it is likely that it will end in a draw as you said. If you look at the two teams
have almost the same strength.