If possible, when would Kagome yell sit at Inuyasha in the Great Valley?
As for Kagome yelling at InuYasha in the Great Valley, trust me. After seeing the series, it doesn't matter what time it is or where they are. When InuYasha does something foolish or mean, Kagome is going to yell at him regardless.
If possible, how do you think Littlefoot and friends, including Guido, get to the fedal era?
As far as getting there, perhaps the legendary LBT magic source- the Stone of Cold Fire- actually exists and it could play some part in the transportation. Perhaps the InuYasha era needed help in places that the group wasn't in, the group was too busy at that time to assisst in smaller crises because they were dealing with a very important issue like a Naraku plot, or something of that nature. Then maybe the stone senses the danger and transports the LBT gang into that time to the place that they could be of use.
If possible, how would Chomper and Guido react toward Inuyash and Kagome?
Now that is a very difficult question. I will have to compare Chomper's and Guido's personalities to those of Kagome and InuYasha to get logical theories on the possibilities that would result in such an interaction. I don't know right off hand, but give me a while and I'll give you my best answer on the topic. When I have it, I will erase the note under this question of yours, and fill in my response. Until then, please bear with me.
Do you think a Land Before Time/Inuyasha crossover on fanfiction would work?
As for an InuYasha/LBT crossover, with all the M rated LBT fanfictions on fanfiction.net, I don't see a problem with the apropriacy matter, so yeah, I can see it as a possibility. Secondly, as for how the gang could be of any use with the InuYasha gang, I could see the gang visiting before the Shikon Jewel- or Jewel of Four Souls- gets destroyed, then perhaps the jewel or even another magic artifact, which are extremely common in that era, could give them magic powers, even demonic ones which seem the most powerful in that series. Yeah, InuYasha has a short temper and likes to get into fights, but so does Cera. And InuYasha swears a lot, but the LBT characters don't have to. In fact, for humor, since the gang has never heard profanity, whenever InuYasha does swear, a LBT character could go, "Huh?", "What does that mean?" or "Is that even a word?" then Kagome, Miroku, Sango, or even young Shippo could say something like, "It deosn't mean anything," When he gets angry, he talks nonsense and says made up words that don't make sense," or "It's just from another language that wouldn't do you any good to learn, so just ignore it." For weapons, I could see Littlefoot holding something in his mouth that could be strapped to his back, or even Ducky holding something like a person does since she has arms. This could be when the gang has grown and matured a little. They may hate fighting now, but perhaps later in their lives they decide that fighting can be the right thing to do if done to protect something or someone that they really care about. Like I said, since it would be a very mature LBT twist if it portrays the InuYasha world, it would definately go into the M rated fanfiction.net section. And since a lot of people like the innocense of the LBT, many people might not be too into a mature version of it. Some InuYasha or mature content loving fans would read it like myself, but almost every other LBT fanfiction there is either K, K+, or teen, if that tells you anything. It would fun to read, but LBT stories with blood, gore, violence, you-know-what themes, and language would probably be a turn off for most LBT fans. I like the idea, but if you want more fans of an InuYasha crossover, I don't think LBT should be the other half and you might want to try elsewear, like a Bleach or Flame of Recca crossover.
Well, you wanted opinions on this matter, and here is my honest one, but of course, anyone is very welcome to disagree with them . Later!