Advice on how to trim / clip stock footage to save space properly

Hello and thank you for taking the time to read this question i have.

Case:  We take lots and lots of stock footage mostly via our UAVs (drones).  We either record in H.264 but mainly in Prores 422 / 4444.  To save space and break up longer clips, what is the best way to export only the parts we want to keep without loosing quality.  We do not want to edit the footage at all and keep it as original (RAW) to sell to our clients.  Is there a way to match the encoding so it doesn't re encode...if that is even possible?

Thank you in advance,

Brocour