I have a friend (not me!) who did it several years ago... from Holland, to France.
each time he returned to France, he sent a few grams of hash in an envelope with a postcard.
for the most part, it arrived at its destination. once (in ten), the mail did not arrive and his girlfriend received a summons to the police station. she said she did not know, and that the envelope was not intended for her... she had no other problems but my friend stopped sending them...
crossing the Holland/France border by car is also very popular!
Lately I've been tempted to pack 6 grams of different hashes in my checked baggage... let's say I did... I would have arrived at my destination with no problem... and even made the return trip with 2 grams... I will have tightened my buttocks several times but I would have been lucky and I will have slipped through the cracks... I will have completed my equipment with cbd flowers bought on site .
but that would have been a hell of a risk... so i will only recommend it if you don't have access to thc at your destination... in my case, i would have spent 2 weeks with my in laws and my wife without thc... might as well cancel my trip directly
but going back to mailing...i think the risk is limited...no big quantities, no flowers...not too often...
you can lose the contents of your parcel of course, but it will be difficult to prove that it was you who sent this parcel... you can always say that you are not aware of anything...
on the other hand... i will hate that you do it because my message reassured you... but that you have a problem!
so weigh the "pros" and "cons" well!