Battery switch between shore charger and battery banks OK?

[japawil]

Greetings to all electrical gurus.
I’m taking the plunge and switching to a LiFePo4 house bank.

The plan is to install a Victron dc to dc charger for when running the engine.
Solar panels fed through Victron MPPT controllers for when away from marina and not running engine.

My question concerns while in a marina.
I have a ProMariner Pronautic 1230P charger, which has lithium settings that will work fine for a 200 amp hour capacity house bank.
My starter battery is an AGM.

Would it be OK to include a Blue Sea 3 position battery switch inline between the shore charger and the house bank with the negative hooked up to common ground busbar and the positives directly to the batteries; one to the lithium house bank and the other to the AGM starter battery, so that I could individually charge the different banks?

The plan would be to keep the AGM attached to the shore power charger when away from the boat for any extended time in order to keep the AGM topped up and happy.
And then have the ability to (after turning off the shore charger, changing the battery selector switch to the lithium house bank, and after resetting the program to lithium, then restarting the shore charger) be able to bring the house bank up to full charge before heading out.
Since lithiums seem to be happiest at a partial charge if sitting for any length of time, it seems prudent to not keep them hooked up to a charger if away for a while.

Is there anything I missed that makes this plan inadvisable?

[smac999]

Feed to the shore charger to the bank with the dc to dc Input.

Let the dc to dc charge the 2nd bank. From Shore and engine.

Then both batteries will charge at the correct voltages.

The direction of the dc - dc is a different question and discussion.

[japawil]

Originally Posted by smac999

Feed to the shore charger to the bank with the dc to dc Input.

Let the dc to dc charge the 2nd bank. From Shore and engine.

Then both batteries will charge at the correct voltages.

The direction of the dc - dc is a different question and discussion.

Thanks.
I had overlooked that there is a remote on/off switch on the dc to dc charger!
So, it should be as simple as leaving it off if away from the boat for a couple months and then switching it back on to bring “dormant” lithiums to full charge before heading offshore.