I am not really sure what exactly the USDA does to determine what comes in or not. I've done a lot of shipping of chinese herbs that I collected myself and sent to the States without any issue. I just label the species and state that is has been "processed". As far as wood, I've always been told to not ship wood with the bark on due to bugs. However, I feel like if I were to seal it up with some poly and make it look processed in this regard, they may not care. The bark on this stuff is like hickory bark: it doesn't like coming off.
These go through x-rays done by Custom officers. Lumber of any form cannot have the following and has restrictions: bug bores, pin holes, rot/punk, heavy spalting, live edge, bark incursion/inclusion, ingrown bark, bark attached, mineralization that shows up “black”, “ghosting trails” such as bug feces. When these don’t pass “clearance” Customs will send you a slip whether you want the following done if they find anything “suspect” about the lumber

: a). quarantine, b). sanitary/phytosanitary inspection or c). destroy. If you choose “b” option there is a fee of $ 40 to fumigate the wood per item if there are in seperate packages. These are the reasons why international packages ends up being longer that expected for delivery due to Customs inspection and administrative formalities. The only way to get around this is to get a professional fumigation service done on your shipment and attached into your package as proof prior to shipping internationally.
Yes, you can put a “clear coat” and list it as a “finished product”..........much more passable in dimensional lumber form. Other forms such as unprocessed form such as short logs, live edge for organic form, well expect the worse......
What I listed above I did not google and these are direct experience- “Land Down Under” is very, very strict and they don’t want anything to get into their country that would result in catastrophic nature that threatens their trees, forest, agriculture, etc.. I never shipped not knowing any of their rules

, matter of fact I alert recipients in what might happen and they still are insistent- damn “wood addicts”

. Some “pin holes” can drive up a red flag. Put it this way, one species was black limba and they red flagged it because of the variegated streaks.
Lesson learned- shipping lumber international is expensive, plus there are associated taxes imposed by the destination country and the possibility of it being flagged by customs will incur additional cost passed on to the importer.