Do some intense sword play without a sensor bar and after that watch Link awkwardly pointing his sword backsides (through you're pointing it forward)... or, try holding sword upwards to charge attack after intense sword play and watch Link failing to do so, pointing his sword in awkward diagonal angles instead. When you have a sensor bar and that occurs, pointing the wiimote forward and still for some seconds is sufficient to recalibrate it (and I confirmed that on a real console too). In fact, I only needed to recalibrate manually (going to menu and coosing recalibrate) only two times during my entire 42 hours play through back when I dumped the game. Also, the game developers wouldn't force you to have the sensor bar to play if it weren't really necessary...
Avell A70 MOB: Core i7-11800H, GeForce RTX 3060, 16 GB DDR4-3200, Windows 11 (Insider Preview)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)