Basically i want to use the HotG and MotF crytals without changing the color of the blade since i cant think of how to do this would it just be easier to make a new saber?

erm, duno what you meen. The HoTg and MoTF crystals have there own separate blade files, it doesn kinda paint over the old blade, you can just retexture those files to the colour you want though. If you dont have kotor tool or dont know how to use it give me your email and ill send you the correct files so you can retexture them.

So i could just replace the texture files with a standard one blue, green etc

yep, u sure can. Just rename the green/blueetc. file to the name of the texture for the two crystals and shuv it in your overide folder. Then it'll be that colour.