Pointers not gonna cause any problem but Fixed guns will cause lots of problem. It will look like hostile ship firing its fixed guns somewhere else but they will hit you.
When haste was Balance Leader, we were planning to make Broadside only capital ships. However not like what you suggest here. This idea can cause lots of PVP issues and can take months to fix
What we decided to do is reducing capital ship weapon amount and giving them new arcs. Like;
+Ships will fire 5% of its weapons to forward and backward, 90% of its weapons to broadside
+Zero fixed broadside weapons
+Cruisers and BCs will have this mechanic aswell
+Maybe slower turn speeds and different ship speeds
+Needs complete capital ship weaponary rework
+Requires lots of Time and Testing
This causes problem though, It will make them very useless against Heavier Ships and Smaller ships. Unless we give weaker ships faster speed and stronger ships slower speed
Also most of discovery capital ships not suitable for Broadside-only combat because of their Design.