I feel like this is the Great Myth of Klonoa fans, lol
No, we don't hate Sonic fans. I don't really keep up with games anymore, but I used to like Sonic games a lot.
I personally prefer the LV outfit (though I think his original outfit is cute too, especially in Moonlight Museum's artwork), and never thought it looked Sonic-y, even when I first discovered him.
Like Rup said, we get a little annoyed when people see him and call him a Sonic character. I can see where the styles are similar in minor areas, but that sort of thing happens all the time. Play one game and you'll see they're completely different entities that aren't really comparable. They're totally different genres, stories, and themes. The only time I get really angry at people is if they look at Klonoa for two seconds and decide, infallibly, that he's a Sonic rip-off with no merits of his own. Even then, I get over it in 5 minutes.
I have a vague hunch where you heard this stuff, and I'm not going to address it. I'm just going to say that we try not to talk about Super Klonoa here, just due to some old drama that we don't want stirred up. Let sleeping dogs lie, etc. I don't think anyone hates SK as a concept, though.
TL;DR no we don't hate Sonic fans, nor Klonoa's LV outfit