Yes you can but how you would to know if this trader transfer this amount to an other person, there is a lot of crypto currency and a lot of adresses, how you would to know what the crypto currency he is buying or selling, so i guess its hard to do it and just a waste of time.
Yes it is but I think it is not good and legal to trace somebody’s wallet and look how much he has and be stolen and hacked. Because the individual wallets are personal property and nobody is allowed to enter into somebody’s property without special request and permission.
Also there are some wallets which cannot be traced due to a strong security. I think all the wallet holders should take the same security.
