Is there any reason lore wise why people can’t just use shape transformation on their chakra and make Susanoo even if they aren’t as large or as power?
I mean all people who have made similar avatars belonged to clans like otsutsuki (ashura’s giant yellow thingy) and Naruto’s use of kcm, besides that idk
Don’t quote me on this but I’m not sure there’s any real way to control the appearance of a chakra avatar (which is what things like Susano’o are considered). But if one has enough chakra and control over it they should be able to produce something of a similar size and power. Like the tailed beast transformations
Educated Guess: It probably consumes A LOT of chakra, and that shape transformations work a little easier when it has a medium of power to work off of. Imagine performing a Water Dragon Jutsu from a large lake. The chakra element, plus chakra control, gives you enough energy and element to create a devastatingly powerful “dragon” to launch. If you used more element - the water - you could make it bigger, or you could create the equivalent of a water cloak, but only under the condition that you’re near a lot of water. In short: The extension of using shape transformation is limited for most; the exception being Jinchuriki and almost every Movie Naruto villain.