Regarding step 2 when you say “based off”, are you creating a child of the original AnimBp, 2 new ones, or copying it, etc.? If you could also post a screenshot of your Blueprints I can take a better look at the issue.
I’ve taken another look a the issue and am unable to reproduce what you are seeing. I’ve posted a screenshot below. However, the Sub-Graph Input is necessary to have set up in order to get the in pose to show up.
I’ve gone ahead and logged it as a bug. If you disconnect the nodes for the Sub Anim Instance < Delete it < re-add it and attach it to the Final Animation Pose < Compile, it should get the pin to appear if you needed a workaround. If you would like to keep an eye on the logged issue, you can do so here in our public tracker.
I’ve taken a look at the issue and followed the repro steps provided but am unable to see any behavior that isn’t intended. I’ve linked some information below on how to set up the anim Blueprints in order to get the pose it sounds like you are looking for. This would use the FABRIK node. If you can give some more details on what you are expecting versus the behavior you are seeing, I can take another look at it.
The Answer is, go to the in pose input not showing anim bp, (the in pose input which belongs to the anim bp) in that anim bp the starting sequence must start with sub graph not default state machine or likte that. This anim bp (starts with sub graph) is not a complete anim bp it does some part of the main anim bp which we are willing use the sub anim instance node. Compile the anim bp go to the main anim bp. This time u will see the in pose is visible.