Power Matching is enabled automatically if you pair your bike power meter. Means your power meter controls the trainer so indoor/outdoor rides are in sync in terms of measured power.
A SMART dynamic power interval is supposed to work that way to ensure you meet the individualized strain goal.
Advanced Workout Design using SMART Intervals – Xert (baronbiosys.com)
Your generated power graph looks normal to me.
Transition response time is a function of the trainer. Some brands offer an option to adjust sensitivity through the trainer’s native app. Same issue applies on either end of the interval (start/end) so net effect should be a wash. Starts a little late, ends a little late.
Example:
Related – Very short intervals and ERG? - General - Xert Community Forum (xertonline.com)