I wanted to know if it is possible to use the negate tool through the use of a script on roblox.
Roblox has implemented UnionAsync and SubtractAsync to create unions in scripts.
In plugins there are additional functions, Seperate, Union, and Negate. These functions can’t be used in normal scripts, but can be used in plugins or through the command bar. If you’re planning to use them in normal scripts, use UnionAsync or SubtractAsync.
These functions are quite expensive, so limit how many times you use them.
Are their any CSG functions that are non-server sided or client sided
No, your best bet is to invoke a remote function on the client to create the union (make sure it can’t be spammed) and then parent to union to replicated storage, return the union to the client, and have the client change the parent to somewhere in workspace. Just make sure to delete the union when its not needed on either the client or the server.