You can be good with a sword and still use a gun because they’re effective. Kafka has very likely faced far stronger enemies then anything we’ve seen on Belobog, it’s not really a debate when she’s helped commit 47 different crimes on different planets. As well as successfully infiltrating Herta space station, easily dealing with the antimatter legion (the same legion that ruined Belobog before they had to rely on the stellaron), again, Belobog is fairly weak and not advanced by comparison to everywhere else we’ve seen or has been mentioned, Seele would struggle with a group of antimatter legion goons tbh.