Bangladesh has an export ban on all firearms & ammunition.
It also has a ban on foreign investment in their arms industry
The BD-08 would require an FRT and despite being a clone would need to go through the Firearms Lab as it is made in a different nation/factory to the Type 81
Bangladesh has ramped down production of the BD-08 and is unlikely to re-design a semi-auto variant which would then need to go for FRT.
It's a nice idea but we're talking a BIG investment, and a multi year wait during a time of liberal happy ban time.
Ordering larger quantities of Type 81 rifles/LMGs than immediately needed when piggybacking on Chinese orders is the best way to maintain supply for time to come. Though it is obviously not fun for immediate cash flow.