How should I tell you... If you didn't know, the primary direction of PrimeXBT is crypto futures and they position themselves as a crypto exchange. Nevertheless, they also provide traditional financial instruments for trading but I hardly believe the conditions on the forex market would be better in comparison to standard forex brokers.
So yeah, you can trade on the forex market here but you better expect nothing special here but I can definitely say the trading on crypto futures is much better than on other crypto exchanges in my opinion.