routing & conversion between 2 networks using different packet sizes (1500 & 9000 bytes)

My computers and switches handle 9k jumbo packets and file transfers go 
faster
between 2 computers using them, however, ran into a slight snag -- IOT 
(Internet of Things): things like media devices, TV, receiver, disc 
player -- all talk ethernet
@ 1.5k packet size.

So I'm wondering, if I setup the devices on a separate subnet and route 
traffic from
my desktop into my server, and have a route to the devices that uses 
1.5k packets, will the networking stack automatically marshal the 9k 
into 1.5k packets for data that gets sent to the 1.5k subnet?  I'm 
guessing it won't automatically do the reverse, but that's not so 
important, since sending 1.5k packets to a 9k destination will just use 
the smaller packets -- its only when I send from a 9k packet enabled
network port to a 1.5k-talking device that I think problems occur 
(occasional random data loss and connection resets).   Does it sound 
like that would work?

I currently have a bridge on the server between 2 networks, one w/9k 
packets and the other with 1.5k packets and that seems to work fine -- 
I'm hoping that's not a coincidence(?)

Thanks!