My reply sticked to that Your part of question:
"Like only using awp, and nothing else? "
I don't think it's not doable to make a weapon restriction. There is a need to add to bots code a cvar which will have some bits responsible for buying/using (it needs work also for pickup) some weapons. If some bit of that cvar is set to 1 - it may means this weapon is banned. So in bot's code such weapon can't be bought or pickuped up according to bit of that cvar. And to control this cvar You can easy write an AMX/AMXX or ClanMod script (this even me - I could do it)
If my C++ coding skill would be at least 10% (now is about 0%), I could do it my-self in bot code...
