Sorry showering is just showering. One cannot by the very nature of baptism be baptized in the shower. Sticking someone in the shower and calling it baptism is like a girl calling themselves a boy. A shower is just a shower
That's the definition of legalism, when what's done in faith doesn't count, but only conformity to unyielding rules count.
The pharisees who condemned Jesus' disciples for picking and eating food on the Sabbath were guilty of legalism. It was the law not work on the Sabbath. The disciples broke unyielding rules which were placed on top of the law. It didn't matter to the Pharisees the circumstances. Maybe the Pharisees argued with Jesus about a slippery slope, that picking food for immediate and personal consumption to treat hunger will lead to people working the Sabbath like any other day of the week. Ideally, the disciples would have preferred their food the evening before, but for whatever reason, they were out of food. Maybe the disciples had given all their food to others that Sabbath day.
The Bible says repent and be baptized, everyone of you. I don't see it written that if you can't do it "the right way" then don't do it all. And, isn't not doing baptism at all rejecting the instruction be baptized? You trade an inability to do the ideal thing for a
willful failure to follow biblical instructions.
If baptism isn't done with submersion, with the right words spoken, and maybe the right water temperature, then it's just getting wet??? On the contrary, if it's done without faith, it's just getting wet. If it's done with faith, it's none of your business how it's done (Romans 14:4).
I tell you, on judgment day, I don't want to be standing with the Pharisees who condemned Jesus' disciples over legalism. On that day, I don't want to explain to Jesus that I didn't obey at all because I couldn't obey him to every detail. On that day, I don't want lean on my works saying I did it right so my faith shouldn't matter.