Ha-ha! The bug-bear of indicators! If price moves sideways too much, signals become unreliable.
I have reverted to using some form of granularity, maybe ATR, so that price needs to move by some minimal amount to be considered a move. Acknowledge the existence of uncertainty in moves.
Trend-plays have to switch to breakout mode. (have struggled for years to codify this, though. Its all eyeballs stuff)
Have been re-visiting Renko charts. (just for fun)
How do you resolve a sideways market?