Well you should really ask rulings in the appropriate forum.... but
Yes Switch & Potion may be played on your Teammate's Pokémon.
When playing a card, if it contains the word "you" or "your", you can play it either on yourself or your partner. Oak's Research states to shuffle your hand into your deck, then draw 5 cards. You can shuffle your hand into your deck & draw 5 or your partner can shuffle their hand into their deck & draw 5. Either way you may not play anymore Supporters this turn.
Fan Club states to search your deck and put up to 2 Basic/Baby Pokémon onto your Bench. So you can search your deck and put up to 2 Basic/Baby Pokémon onto your Bench or your partner can search their deck and put up to 2 Basic/Baby Pokémon onto their Bench. Either way you cannot play any more Supporters this turn.