Let's assume a E form barre chord...
If you are playing on roots like G, G#, A, A#, B..., that might not be an effective practice pattern for two reasons:
- The distance is only one fret. This may be too easy for you. When you can execute this without trouble repeating it for practice is sort of a waste of time.
- Two major chords connected by a half step is a little uncommon, three or more in a row is definitely not common. You're missing the aural reinforcement - the musical reward you could call it - of hearing "real" chord progressions when you execute the change correctly.
You're 4th fret to 9th fret change is a good "real" progression. It's a root change by 4th,
If that feels too far, try instead dropping down 2 frets
F#. Of course it's a shorted distance and so should be easier. But also it's a "real" progression. Hopefully that will give you positive musical feedback.
Eventually you can try combining all three
C#. The are all in the same key and so will sound like real music.
But you can try some other things beside just altering the distance you must slide.
The first obvious thing to alter is the tempo. Slow down the beat and experiment with just how slow you need to go before you can make the change. While it may sound counter-intuitive also try going faster! Focus hard and try to speed it up just for a few repeats, then drop back down to normal tempo. The idea is to acclimate yourself to a faster speed in gradual stages.
Where you're looking
Where are you looking? Probably at your hand making the barre chord. Try to not look at that hand and make the short 1 or 2 fret changes. Instead of seeing the distance you want to feel the size of the shift of your forearm.
If you do look, try to look at the target not your hand. If you are already on the 4th fret, what good does it do to look at your hand? It's already in place. Look at the empty place of the 2nd or 9th frets and then watch your hand with your peripheral vision move into place.
Part of the problem might be your "grip" on the barre chord while changing position. You want to release your grip for the change, but without your fingers falling out of the E form shape. You want minimal movement in the release, sort of a lightness in the grip. If that seems like a problem trying keeping the chord in place on a fret and then play it staccato where you squeeze the grip just for a moment to create the short staccato effect. A kind of bouncy squeeze for 4 or 8 strokes then change the chord. The point is to try to develop the slightest of movement and speed to release the chord without loosing the chord shape.