All you need to do is drag a Fade transition onto the junction between the clips. You may want to experiment with the duration of the transition and change its behavior from Cross to Overlap (or vice versa) to get the kind of blending you want.
Note that if the transition is set to Overlap, you might want to extend the first clip a bit and start the trailing clip a little sooner so that the content you want is clear of the transition since both clips will be blended together there.
YouTube/optodata
DS365 | Win11 Pro | Ryzen 9 3950X | RTX 4070 Ti | 32GB RAM | 10TB SSDs | 5K+4K HDR monitors
Canon Vixia GX10 (4K 60p) | HF G30 (HD 60p) | Yi Action+ 4K | 360Fly 4K 360°