Not really a good comparison for division (pothos vs peperomia).
The answer is "probably yes" but the plant is terribly fragile and you could expect a degree of collateral stem and leaf damage.
You could saw right through the rootball with a sharp clean knife - however until you remove it from the pot it will be difficult to know exactly where to do that. You would need to try to disturb the plant and the roots as little as possible and preferably make it a 2-man job with someone holding the plant and then dropping one half into a new pot and you backfilling.
However, since it is such a nice plant right now, and set-back is probably likely, why not simply move it into a larger pot if you think it is cramped?