Clause 7.2.2 in the trading manual for RSS (Regulated Short Selling) specifically:

"POs must open and use a designated trading account (RSS trading accounts) for RSS orders. Normal orders and Direct Business Transactions (DBTs) are not allowed in RSS trading account. With the exception of :
a) erroneous trades on non-RSS approved securities and shares of non-RSS approved securities credited into the designated RSS account arising from corporate action. To facilitate rectification, normal buy and sell would be allowed to close off such positions. The PO is required to report such cases if any in the Monthly Compliance Report.
b) normal buy transactions of RSS approved securities in the RSS account are for return only."

Normal buy transaction of RSS securities are for return only...still DBT IS NOT ALLOWED

Is off market transaction allowed? see the link below on bursa's trading manual

https://www.bursamalaysia.com/sites/5d809dcf39fba22790cad230/assets/5fcdabe439fba27a9596b8f6/POs_Trading_Manual_v27_Final_highlighted.pdf

Clause:
"7.1.3 Short selling is only applicable to Normal Market, and not allowed for Odd lot, Buying-in and DBT markets."

So DBT markets (direct business transactions) are not allowed