Can nasolabial subcision cause sagging later on?

It sounds like you are referring to a release of the nasolabial fold attachments.  This is often done with a fine surgical wire.  The results are a little hit or miss, but I don't think it will accelerate sagging.

Thank you for your question. This procedure will not lead to premature aging in the area.  It is also not going to make much of an improvement.  You will get temporary swelling and bruising.  The swelling will initially look like there has been meaningful improvement, but the fold will return shortly thereafter.  The anatomy of the tear trough is complex and freeing the skin from the underlying attachments is not in itself very helpful.  On the other hand, if you are referring to abscission in that area because of scar tethering such as old acne, then yes, it can be effective and long lasting.