
Probably one of the easiest conversions so far for Mass Effect Rogue Space has been in the weapons department. In the Rogue Space rulebook there is a very large selection of weapons, both melee and ranged. I just took the ME equivalent, figured out which Rogue Space gun was the closest in scope, and mashed up the two with some minor tweaks as needed. If you haven't figured out by now, I take the laid back approach to conversion, not the "easy" route mind you, just not the "going to reinvent the wheel from scratch" route either.
Stat blocks for Rogue Space weapons are fairly straight forward as well. As for ammo, since everything in the ME universe seems to run off of thermal clips, we will just keep track of how many rounds a particular gun holds, then reload with these universal thermal clips.

Manufactured by Elanus Risk Control, the Predator is valued as a powerful, deadly, and relatively inexpensive weapon. While it is not generally deployed in the military, due to commonality of kinetic barriers, it’s still very popular in the Terminus Systems where these defenses are less common.

The M5 Phalanx is the product of the Alliance's Offensive Handgun Project that developed a close-in weapon to be used on armored or shielded targets with no loss of stopping power in comparison to the soldier's assault rifle. The Phalanx enjoys a ballistics advantage even over most "hand cannons" and features an integral laser sight which is highly visible even in bright lighting conditions.

Common military shotgun. Deadly at short range, but ineffective at long range. Very effective versus shields and biotic barriers, but weak versus armor. Manufactured by Ariake Technologies, the Katana is a common mercenary weapon.

Manufactured by Devlon Industries, the Mantis is primarily used by police and planetary militia groups. The prevalence of kinetic barriers has made this weapon less popular with the military, but it is used more frequently in the Terminus systems where these defenses are less common.

As kinetic barriers have grown in popularity, so has the popularity of submachine guns. Manufactured by the Elkoss Combine, the Shuriken machine pistol has a reputation for being deadly and easy to use, but is weak against armor.

The Krogan combat axe is both a ceremonial symbol as well as a devastating hand-to-hand weapon. Made of modern synthetic polymers and carbides, it is able to penetrate the toughest of armored opponents, especially with the full strength of a Krogan behind it.

The standard combat knife comes in many forms but the premise is universally the same; it slices, it dices. Often carried as part of the soldier's kit, the combat knife is useful as a tool, a hand-to-hand weapon, and more. In the right hands it can also be used as a thrown weapon, albeit with a severely limited range.
Across the Mass Effect franchise there are dozens of rifles, pistols, and more. On top of that you further modify your weapons with all manner of additional equipment like scopes, barrels, heat sinks, and more. Then there's a half dozen different ammo loads to boot. Needless to say, this only scratches the very tip of the iceberg when it comes to ME weapon conversions. It's enough to get the troopers, err, players started however, and once they start bagging some Geth they'll get upgrades I'm sure. Speaking of Geth, next time we will look at putting these bad guys on paper to duke it out with the NPCs.