Would a token that plans to take an additional percentage Lumens for transaction fees be possible to create on the existing Stellar network?
No, it's not possible. The maximum you can do is to control who is allowed to purchase your token with AUTHORIZATION REQUIRED flag.
Yes, Imagine I Want to Tokenize Shares/Commodities but Not Build My Own Exchange to Allow Commissions.(Like Kinesis) But Rather Collect 0.5% of Every SDEX Transaction of My Issued Tkns. The Seller Sells Bob 100 Tkns & Bob Receives 99.5; The Issuer of Tkns Receives 0.5 Tkns.
I'm Thinking of a Way Some Investment House(Interactive Brokers) Would be Incentivised to Issue Equity backed Tokens to be Traded on SDEX. Those Starting on this Task Are Establishing Their Own Exchanges That Do Not Contribute to Stellar Volume & Their Tokens Will NOT be Accessible on SDEX / StellarX / Lobstr Wallet etc.