So i want to make a filling by folding fresh raspberries into buttercream but im worried about the seeds. Has anybody done this and had issues of biting into seeds? I don't like the cooked gel fillings so im trying to figure out if this way will work? Thanks!

What about making a raspberry puree and adding it to buttercream making a raspberry buttercream? After you cook the raspberries down, push it all through a fine mesh strainer. Let it cool then mix w/ b'cream.