knx.send s payload doesn’t accept entity_ids. It would read them as string. You can, however, use templates there.
For those complex DPTs you’d have to pass a dict containing the right keys. Afaik, this isn’t documented anywhere, so you’d have to look it up in the code xknx/xknx/dpt/dpt_10.py at 60e0523513afbe773711bf9b2d37cc55aa7d467c · XKNX/xknx · GitHub
Or, as I already pointed out in your GH issue, just use a knx time entity.
PS: Have a look at How to help us help you especially § 11 and 16.