Im not sure but we can add +relay_host condition to my config? Or something similar.
Well, the problem is that you're making it more complicated. Each time someone decides to change the SPF record to allow another sender, you'll have to add a relay_host condition. And I think this will only get worse when adding outlook365 servers, external antispam relays, etc.
In fact you'll be crafting a copy of some spamblocker/spamassassin parts.
I'd change the '~all' in the SPF to '-all' and simply have every mailserver (not listed as allowed sender in the SPF) get denied by the antispam software.
That keeps stuff RFC compliant, less documentation/complexity and you don't have to make all the changes again when updating the exim configs.
But maybe it's easy done in exim. We have never needed it, so I can't help you with that, sorry