Thank you for quickly replying.
But my issue is not related to boolean,polygroup’s advantage and fusing&welding
It’s just simple,I have two meshs,all 5 levels and detailed,all have hard edges that are creased,not fuse and weld,they do not coincide,just two parts,and after merging in level 5,the levels and details are merging well,but the crease is gone,so when I change to level 1 the new merged mesh will deform
I know that there are problems in this workflow,I should think over my subtool arrangement before I start to subdivide and sculpt.
But the die is cast,I just want to merge these two 5-level subtools with crease
And I also know I could just ignore it and just export low and high and just combine it again,then bake as usual or just after all work done,then combine low and high seperately.
But it’s just not intuitive,I just want to simply combine them and drag my mouse from level 1 to 5 to 1 without creasing gone and lowpoly deforming.